Physics Assessments QUARTER ONE Unit One P2.1A Calculate the average speed of an object using the change of position and elapsed time. L2 1. The picture shows the position of a ball every 0.25 second on a photogram. Using a ruler, determine the velocity of the ball. A. B. C. D. 3.5 cm/s 10.5 cm/s 14.0 cm/s 28.0 cm/s Answer: B 2. What is the average velocity of the boat over the time interval shown? A. B. C. D. Position (m) 25 22.5 20 17.5 15 12.5 ∆12.5 m/s ∆1.25 m/s 1.25 m/s 12.5 m/s Answer: B Time (s) 1 3 5 7 9 11 3. What can be concluded about the motion of the boat from the given data? A. B. C. D. The boat is driving towards the 0m location. The boat is driving backwards towards the finish line. The boat is accelerating towards the 0m location. The boat is driving in circles around the 0m location. Answer: A Physics Assessments – August 2008 Revision 1 4. Four cities all lie along a straight line as shown in the diagram. A delivery driver departs from City B, drives to City D, and then Drives to City A. The total time for the trip is 0.70 hours. What is the driver’s displacement at the end of the described trip? A. B. C. D. 5 miles 11 miles 21 miles 37 miles Answer: A 5. What distance does the driver cover during the described trip? A. B. C. D. 11 miles 21 miles 37 miles 42 miles Answer: C 6. What is the driver’s average velocity during the described trip? A. B. C. D. 7.1 mi/hr 30 mi/hr 52.9 mi/hr 60 mi/hr Answer: C 7. What is the driver’s average speed during the described trip? A. B. C. D. 7.1 mi/hr 30 mi/hr 52.9 mi/hr 60 mi/hr Answer: C Physics Assessments – August 2008 Revision 2 P2.1B Represent the velocities for linear and circular motion using motion diagrams (arrows on strobe pictures). L2 t=0s t=5s t=0s t=4s A B The diagram above represents the position of two bowling balls (A & B) at one-second intervals. The arrows are 2.0 meters apart. 1. What can you observe about the motion of the two bowling balls? A. B. C. D. Both balls move at the same velocity. Ball A moves faster than Ball B. Ball A moves slower than Ball B. Neither ball is moving. Answer: C 2. What is the average velocity of Ball A? A. B. C. D. E. 5.0 m/s 4.0 m/s 2.5 m/s 2.0 m/s 1.0 m/s Answer: D 3. What was the average velocity of Ball B? A. B. C. D. E. 5.0 m/s 4.0 m/s 2.5 m/s 2.0 m/s 1.25 m/s Answer: C Physics Assessments – August 2008 Revision 3 4. A skateboarder is rolling down the side walk as shown in the diagram below. We can infer from this diagram that the skateboarder is A. B. C. D. moving at a constant speed. moving at a constant acceleration. The arrows are oriented in the direction of motion showing a negative motion. The direction of the motion is unclear from the diagram. Answer: A 5. Study the diagram below and determine which of the objects are undergoing an acceleration. A. B. C. D. B and D are experiencing acceleration B, D and E are experiencing acceleration A only is showing acceleration None of the diagrams are showing acceleration Answer: B Physics Assessments – August 2008 Revision 4 P2.1C Create line graphs using measured values of position and elapsed time. L3 1. Which equation best represents the motion depicted by the data? A. B. C. D. Time, t (s) x = (150m/s)t + 0m x = (150m/s)t + 50m x = (30m/s)t + 0m x = (30m/s)t + 50m 0 5 10 15 20 Answer: D 2. What is the average velocity of the car? A. B. C. D. Time, t (s) 30m/s 35m/s 40m/s 50m/s 0 5 10 15 20 Answer: A Position, x (m) 50 200 350 500 650 Position, x (m) 50 200 350 500 650 P2.1D Describe and analyze the motion that a position-time graph represents, given the graph. L2 1. The distance vs. time graph below shows data collected as a remote-controlled car moved across a level parking lot. According to the graph, which of the following conclusions about the car's motion is supported? A. The car is accelerating B. The car is stopping and starting C. The car is traveling at a constant velocity D. The car is moving through an obstacle course Answer: A Physics Assessments – August 2008 Revision 5 2. What is the object’s average velocity from t = 0s to t = 8s? A. B. C. D. 0.44 m/s 0.51 m/s 0.77 m/s 1.75 m/s Answer: C 3. What is the object’s velocity at t = 8s? A. B. C. D. ∆1.33 m/s ∆0.75 m/s 0.75 m/s 1.33 m/s Answer: B 4. The motion of three objects (Object A, Object B, and Object C) is described by the three lines on the position-time graph at the right. Which one of the objects is moving with the greatest speed? A. B. C. D. Object A Object B Object C Hard to tell with this diagram Answer: A 5. While on vacation, Lisa Carr traveled a total distance of 440 miles. Her trip took 8 hours. What was her average speed? A. B. C. D. 18 miles/hour 80 miles/hour 60 miles/hour 55 miles/hour Answer: D Physics Assessments – August 2008 Revision 6 6. Starting from rest, a car undergoes a constant acceleration of 6 m/s2. How far will the car travel in the first second? A. B. C. D. 6 meters 3 meters 1 meter 2 meters Answer: B P.1.1g Based on empirical evidence, explain and critique the reasoning used to draw a scientific conclusion or explanation. P2.1g Solve problems involving average speed and constant acceleration in one dimension. L2 1. Objects A and B are dropped from rest near Earth’s surface. Object A has mass m and object B has mass 2m. After 2 seconds of free fall, object A has a speed v and has fallen a distance d. What are the speed and distance of fall of object B after 2 seconds of free fall? A. B. C. D. speed = v/2 ; distance = d/2 speed = v; distance = d speed = v/2 ; distance = 2d speed = 2v; distance = 2d Answer: B 2. Becky rode her bicycle 300.00 meters due east in 30.0 seconds. She then peddled directly south for 20.0 seconds at the same speed. She then peddled 50.0 meters directly north in 5.00 seconds. A. B. C. D. What was the total distance that she peddled her bicycle? What was her average speed? What was her displacement? How would you determine her average velocity? A. B. C. D. Total distance = 300 m + 200 m + 50.0 m = 550 m (2pts) 10 m/s 335.4 m -- 26.6¡ south of due east total displacement divided by total time Answers: Physics Assessments – August 2008 Revision 7 3. The data given below were collected from two different objects. The differences in the two objects can be explained as A. Object A is constant velocity while Object B is constant acceleration B. Both objects start at the same location at the same time C. Both objects are moving in the same direction D. All of the above Answer: D Time (s) 0.00 0.25 0.50 0.75 1.00 1.25 1.50 1.75 2.00 Object A Position (m) 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 Object B Position (m) 0.000 0.094 0.375 0.844 1.500 2.344 3.375 4.594 6.000 P2.2A Distinguish between the variables of distance, displacement, speed, velocity, and acceleration. L2 1. An object is observed to have zero acceleration. Which of the following statements must be true? A. B. C. D. The object is motionless. The object is moving in a circular path. There is no friction acting on the object. The object has a constant velocity. Answer: D 2. A car driving down the freeway has a constant velocity. Which of the following statements must be true? A. B. C. D. The car has zero acceleration. The car is moving in a circular path. There is no friction acting on the car. The car is speeding up. Answer: A Physics Assessments – August 2008 Revision 8 3. The following table gives the position of a boat at various times. How can the motion of the boat best be described? A. The boat has a constant, non-zero velocity. B. The boat has zero velocity, but non-zero acceleration. C. The boat has a constant, non-zero acceleration. D. There is insufficient data here to accurately describe the boat’s motion. Position (m) 25 22.5 20 17.5 15 12.5 Time (s) 1 3 5 7 9 11 Answer: A 4. One of the oldest rides at an amusement park is the Merry-go-round. It is a favorite of very young children, but not exciting enough for high school age students. There is still much physics that can be studied with the Merry-go-round. Consider the following Merry-goround. The inner radius of the rider’s platform is 10 ft. The outer radius is 20 ft. There are four rows of animals to ride in that 10 foot distance on the platform. When the Merry-goround is moving at full speed it takes just 40 seconds to make a complete rotation. Some of the horses on the Merry-go-round move up and down in a periodic manner. The horse on the innermost row of animals is located 12.0 ft from the center of rotation. The horse on the outermost row of animals is located 18.0 ft from the center of rotation. Answer the following as it relates to the above. The person riding on the inner horse would feel an acceleration that is A. B. C. D. zero once the ride gets up to speed the same as the acceleration of a person on the outer horse about 2/3 the acceleration of a person on the outer horse about 3/2 the acceleration of a person on the outer horse Answer: D 5. The kinetic energy of a person riding on the inner row as compared to the kinetic energy of the same person riding on the outer row A. B. C. D. is the same since they both take the same time to make one revolution. is equal to the ratio of their respective radii of rotation. is equal to the inverse ratio of their respective radii of rotation. is equal to the ratio of the square of their respective radii of rotation. Answer: D Physics Assessments – August 2008 Revision 9 6. One of the easier rides at a local amusement park is the steam engine driven train. The train follows the track shown in the diagram below. The total length of the track is 1.4 miles. It takes the train 12.0 minutes to cover the length of the track. The train takes 4 sec. from stop to reach its speed, which it then maintains through the entire course until it takes 6 sec. to stop back at the station. Answer the following questions as they relate to the above. If you are going to determine the force acting on you at point B on the track you will need to know all of the following except A. B. C. D. the radius of curvature of the track at point B the speed you are moving at point B your mass how long it took you to get to point B from the station. Answer: B 7. The average velocity of the train during the 12 minute ride is A. B. C. D. zero 11.7 mi/hr 7.0 mi/hr 10.3 ft/s Answer: A 8. The average speed of the train during the 12 minute ride is A. B. C. D. zero 11.7 mi/hr 7.0 mi/hr 10.3 ft/s Answer: C Physics Assessments – August 2008 Revision 10 P2.2B Use the change of speed and elapsed time to calculate the average acceleration for linear motion. L2 1. A ball starting from rest accelerates uniformly at 5.0 meters per second as it rolls 40 meters down an incline. How much time is required for the ball to roll the 40 meters? A. B. C. D. 2.8 s 8.0 s 16 s 4.0 s Answer: B 2. The speed of a car is decreased uniformly from 30 meters per second to 10 meters per second in 4.0 seconds. The magnitude of the car’s acceleration is A. B. C. D. 5.0 m/s2 10. m/s2 20. m/s2 40. m/s2 Answer: A 3. What is the average acceleration of a car that goes from rest to 60 km/hr in 8 seconds. A. B. C. D. 8 km/hr ∙s 13 km/hr ∙s 7.5 km/hr ∙s None of the above Answer: C 4. How long does it take to accelerate an object from rest to 10 m/s if the acceleration was 2 m/s2? A. B. C. D. 10 seconds 5 seconds 15 seconds 2 seconds Answer: B Physics Assessments – August 2008 Revision 11 5. Carl started to run at 10 km/h when he left his house. He arrived at school 30 minutes later. How fast was he running when he arrived there? Assume that his average acceleration was 30 km/h2. A. B. C. D. 25 km/h 3 km/h 1 km/h 30 km/h Answer: A P2.2C Describe and analyze the motion that a velocity-time graph represents, given the graph. L2 1. The graph below shows the velocity of a car over a period of six hours. What is the car's acceleration between hours 2 and 3? A. B. C. D. 0 km/h2 – 10 km/h2 20 km/h2 10 km/h2 Answer: D 2. A graph of a car's motion is shown below. Which statement best describes the car's motion between 3 seconds and 6 seconds? A. B. C. D. The car is accelerating The car is decelerating The car has a constant velocity The car is stopped. Answer: B Physics Assessments – August 2008 Revision 12 3. What is the instantaneous acceleration of the object when t = 0 in the diagram below? For example, the instantaneous acceleration when t = 3 at the below graph is 3 m/s2, since the graph has a slope of 3 when t = 3. A. B. C. D. 4 m/s 3 m/s 0 m/s 1 m/s Answer: A 4. For example, the instantaneous acceleration when t = 3 at the below graph is 3 m/s2, since the graph has a slope of 3 when t = 3. What is the average acceleration of the whole trip? (When t = 7, velocity = 26 m/s) A. B. C. D. 18.2 m/s2 4 m/s2 3.7 m/s2 26 m/s2 Answer: C Physics Assessments – August 2008 Revision 13 P2.2e Use the area under a velocity-time graph to calculate the distance traveled and the slope to calculate the acceleration. L2 1. Based on the data in the table below, which graph best represents the area under the velocitytime graph that calculates the acceleration based on distance traveled and the slope. A. B. C. D. Answer: A Physics Assessments – August 2008 Revision 14 2. Which graph best depicts a car traveling at a steady velocity of 65 mph for 3 hours. A. B. C. D. Graph #1 Graph #2 Graph #3 Graph #4 Answer: A 3. Based on the graph below, find the distance traveled from the area below the velocity-time graph. The velocity of the car, v ms-1 modeled by v = 2-0.5√t for 0 = t= 16. A. B. C. D. 2 meters in 10 second intervals 5 meters in 2 second intervals 8 meters in 2 second intervals 10 meters in 2 second intervals Answer: D 4. Find the distance traveled modeled by the area under the velocity-time graph A. B. C. D. 58 meters 45 meters 3 meters 116 meters Answer: B Physics Assessments – August 2008 Revision 15 2.3x Frames of Reference All motion is relative to whatever frame of reference is chosen, for there is no motionless frame from which to judge all motion. P2.3a Describe and compare the motion of an object using different reference frames. 1. Jane is driving north at 20 m/s. Betty is driving south at 15 m/s. How would the observed motion of each driver compare, relative to each other? A. B. C. D. Each driver observes the other at 35 m/s, relative to herself. Each driver observes the other at 5 m/s, relative to herself. Jane sees Betty driving at 20 m/s; Betty sees Jane driving at 15 m/s. Jane sees Betty driving at 15 m/s; Betty sees Jane driving at 20 m/s. Answer: A 2. An airplane drops a rescue pack to a group of stranded hikers. What type of path do people in the plane observe that the packet follows? A. The packet falls straight down vertically from the plane. B. The packet takes a straight diagonally downward path. C. The packet flies horizontally with the plane for a time and then falls diagonally downward. D. The packet falls downward in a parabola-shaped path. Answer: A 3. An airplane drops a rescue pack to a group of stranded hikers. What type of path do the hikers observe that the packet follows? A. The packet falls straight down vertically from the plane. B. The packet takes a straight diagonally downward path. C. The packet flies horizontally with the plane for a time and then falls diagonally downward. D. The packet falls downward in a parabola-shaped path. Answer: D Physics Assessments – August 2008 Revision 16 Unit Two P3.1A Identify the force(s) acting between objects in “direct contact” or at a distance. L1 1. A car is parked on the side of a hill. Which of the following most likely prevents the car from moving down the hill? A. B. C. D. The car has too much mass to move easily. There is friction in the door hinges of the car. There is friction between the tires and the road. The weight of the car is mostly on the front wheels. Answer: C 2. What force is acting throughout the length of the rubber band shown below? A. B. C. D. kinetic force frictional force torque tension Answer: D 3. What force indicated by the X on the diagram is helping to hang this plant from the ceiling? A. B. C. D. torque electrostatic tension friction Answer: D 4. What force acting on the block is labeled B in the diagram below? A. B. C. D. normal tension friction gravity Answer: B Physics Assessments – August 2008 Revision 17 P3.1d Identify the basic forces in everyday interactions. L1 P1.1f Predict what would happen if the variables, methods, or timing of an investigation were changed. 1. Each of the following situations describes some kind of motion. Identify which of Newton’s three laws of motion might best explain the motion. a. 1st Law: Law of Inertia b. 2nd Law: F = ma c. 3rd Law: Action/Reaction ______ 1. A child riding without a safety restraint is propelled through the windshield of the car when it is involved in an accident. ______ 2. Your friend lets you shoot his new shot gun and it makes your shoulder sore. ______ 3. A car on an icy road slides off the road while trying to negotiate a curve. ______ 4. After sitting in class for nearly an hour you are ready to announce that you are suffering from tired bottom. ______ 5. A drag race is mostly all engine and tires. ______ 6. You have to walk to town after your car becomes stuck in the sand and you are unable to push it out. ______ 7. A fighter plane uses a drag parachute to aid in stopping. ______ 8. In a fit of anger you swing your fist at the wall putting a hole in the wall and breaking your hand. Answers: 1. a 2. c 3. a 4. c 5. b 6. a 7. b 8. c Physics Assessments – August 2008 Revision 18 A steel block is pulled along a steel surface. An experiment is conducted that compares the forces needed to overcome friction when the weight is changed. Block weights 10kg 1.5kg 5kg 0.75kg Smooth steel surface 15kg 2.25kg Answer the following questions as they relate to the above. 1. What happens to the frictional force as the weight of the block increases? A. B. C. D. The frictional force stays the same. The frictional force increases. The coefficient of friction increases. The coefficient of friction decreases. Answer: B 2. Which graph depicts the change in frictional force of the smooth steel surface? A. B. C. D. E. Answer: C Physics Assessments – August 2008 Revision 19 (also with P 3.1d) P1.1f Predict what would happen if the variables, methods, or timing of an investigation were changed. Some students conducted experiments using different brands of adhesive tape, one kind each of paper and plastic, a board, and a spring scale. Experiment 1 A student stuck one end of a piece of tape onto the edge of a board that was wrapped with paper. The other end of the tape was clamped to a spring scale, as shown in Figure 1. While one student held the board, a second student pulled the spring scale until the tape came off the paper wrapping; a third student recorded the force in newtons, N, indicated on the spring scale at the moment the tape came off the paper wrapping. The procedure was repeated for 3 different brands of tape; each brand of tape came in many different widths, of which 2 or 3 were tested. The results are in Table 1. Tape brand X Y Z Tape width (cm) 1.0 2.0 3.0 2.0 2.5 1.0 2.0 Table 1 Force (N) to remove tape: Trial 1 Trial 2 Trial 3 Average 1.6 3.9 6.0 4.0 5.4 2.2 4.1 1.9 3.7 5.6 4.5 5.1 1.6 3.9 2.2 4.1 5.8 4.3 5.7 1.8 3.6 1.9 3.9 5.8 4.3 5.4 1.9 3.9 Experiment 2 The students performed an experiment similar to Experiment 1, except that the paper wrapping was replaced by a plastic wrapping. The results are shown in Table 2. Tape brand X Y Z Tape width (cm) 1.0 2.0 3.0 2.0 2.5 1.5 Physics Assessments – August 2008 Revision Table 2 Force (N) to remove tape: Trial 1 Trial 2 Trial 3 Average 1.7 3.2 5.0 4.3 5.5 2.8 20 1.5 3.2 5.0 4.3 5.4 2.8 1.6 3.3 5.1 4.3 5.4 2.9 1.6 3.2 5.0 4.3 5.4 2.8 1. The results of the two experiments support the conclusion that, for a given brand of tape, as the tape’s width increases, the force required to remove the tape from a given wrapping: A. B. C. D. increases only. decreases only. remains constant. varies, but with no particular trend. Answer: A 2. In Experiment 2, had Brand X tape in a 4.0 cm width been tested, the force required to remove the tape from the plastic wrapping would have been closest to: A. B. C. D. 5.0 N. 7.0 N. 9.0 N. 11.0 N. Answer: C 3. Based on the average results of Experiments 1 and 2, which of the following brands of tape adhered better to the paper than to the plastic? A. B. C. D. Brand X Brand Y Brands X and Y Brands Y and Z Answer: A 4. Which brand(s) of tape was/were used at only 2 different widths in both experiments? A. B. C. D. Brand X only Brand Y only Brand Z only Brands Y and Z only Answer: B Physics Assessments – August 2008 Revision 21 5. For the students to determine the force required to remove tape from a wrapping, which of the following attractive forces had to exceed the adhesive force between the tape and the wrapping? A. B. C. D. The force between the clamp and the tape. The force between the clamp and the paper or plastic wrapping. The force between the Earth and the wrapping. The force between the Earth and the tape. Answer: A 6. The students’ instructor have them a strip of tape that was 2.5 cm wide and asked them to identify the brand. The students repeated the procedures from Experiments 1 and 2 using the tape and obtained average forces of 4.9 N for paper and 4.1 for plastic. Which of the following brands would most likely have produced these results? A. B. C. D. Brand X only Brand Y only Brands X and Y only Brands Y and Z only Answer: A P3.2A Identify the magnitude and direction of everyday forces (e.g., wind, tension in ropes, pushes and pulls, weight). L2 1. Two boys wearing in-line skates are standing on a smooth surface with the palms of their hands touching and their arms bent, as shown above. If Boy X pushes by straightening his arms out while Boy Y holds his arms in the original position, what is the motion of the two boys? A. B. C. D. Boy X does not move and Boy Y moves backward. Boy Y does not move and Boy X moves backward. Boy X and Boy Y both move backward. The motion depends on how hard Boy X pushes. Answer: C Physics Assessments – August 2008 Revision 22 2. A parachutist in free fall first reaches terminal velocity A. B. C. D. at the time of collision with the earth when the force of gravity is greater than the air resistance when the force of gravity is just balanced by the air resistance after the parachute is opened. Answer: C 3. During an experiment, you notice that as you increase the mass on a spring scale (used to measure weight) that the reading on the scale also increases. Which statement best describes the relationship between the variables in this experiment? A. B. C. D. Weight directly influences the amount of mass. Mass has little influence on weight. As mass increases, weight will increase. Weight and mass are identical. Answer: C 4. Identify of action-reaction force pairs in the following diagram. A. The elephant's feet push backward on the ground; the ground pushes forward on its feet. B. The right end of the right rope pulls leftward on the elephant's body; its body pulls rightward on the right end of the right rope. The left end of the right rope pulls rightward on the man; the man pulls leftward on the left end of the right rope. \ C. The tractor pulls leftward on the right end of the left rope; the left end of the left rope pulls rightward on the tractor. D. All of the above Answer: D Physics Assessments – August 2008 Revision 23 5. Consider the interaction depicted below between foot A, ball B, and foot C. The three objects interact simultaneously (at the same time). Identify the two pairs of action-reaction forces. Use the notation "foot A", "foot C", and "ball B" in your statements.. A. B. C. D. E. Ball presses down on the ground and ground pushes up on the ball. Foot A pushes ball B to the right; and ball B pushes foot A to the left. Foot C pushes ball B to the left; and ball B pushes foot C to the right A and B B and C Answer: E P3.2C Calculate the net force acting on an object. L2 1. Which of the following will definitely cause a change in the velocity of a parked car? A. B. C. D. The car experiences an unbalanced force. All forces acting on the car increase by 1 N. All forces acting on the car decrease by 1 N. The forces acting on the car are equal and balanced. Answer: A 2. The forces acting on a skateboarder moving at a constant velocity along a sidewalk are shown in the figure below. Normal force = 600 N Weight of skateboarder = 600 N Which of the following is the net force on the skateboarder? A. B. C. D. 0N 670 N 70 N 1270 N Answer: A Physics Assessments – August 2008 Revision 24 3. Use the free body diagram below to answer the question. Assuming the surface is frictionless, which vector shows the correct net force acting on the block? A. B. C. Answer: B P3.2d Identify the basic forces in every interactions. L1 1. A box is at rest on a hill. What is the correct vector diagram? A. B. C. D. Answer: C Physics Assessments – August 2008 Revision 25 D. 2. Different masses are hung on a spring scale calibrated in Newtons. The force exerted by gravity on 5 kg = ______ N. A. B. C. D. 49 N 10 N 5N 50 N Answer: A 4. Which diagram (situation A, B, C, or D) illustrates a net force of 5 Newtons, left? Answer: B Physics Assessments – August 2008 Revision 26 4. A Girl is suspended motionless from the ceiling by two ropes. A free-body diagram for this situation looks like this: (choose A, B, C, or D) A. B. C. D. Answer: B P3.3A Identify the action and reaction force from examples of forces in everyday situations (e.g., book on a table, walking across the floor, pushing open a door). L1 1. A ball having a mass m is struck by a bat having mass 9m. Compared to the magnitude of the force exerted by the bat on the ball, the magnitude of the force exerted by the ball on the bat is A. Less B. Greater C. The same Answer: A Physics Assessments – August 2008 Revision 27 2. The sketch below shows two windows. The left window has been cracked by a flying stone. A tennis ball, with the same mass and speed as the stone, strikes the adjacent, similar window, but does not crack it. Which answer is not correct? A. there is a longer collision impact time and (therefore) smaller force for ball than stone. B. The surface area struck is greater on the tennis ball than on the stone. C. The shape of the stone has ridges and edges and can crack things. D. ball is soft and when it strikes the window it absorbs some of its own velocity and rebounds back. Answer: A 3. Some high heeled shoes are claimed to damage floors. The base diameter of these very high heels is about 0.5 cm and of ordinary heels about 3 cm. Which answer most correctly explains why high heels may damage floors? Why does this happen? A. B. C. D. The heels are very sharp and will cause marks on the floor There is greater pressure on the floor because of smaller area of the heels. The heels have a smaller area, that's why they cause damage to floors. A decrease in area increases the hardness of the heels. Answer: B Physics Assessments – August 2008 Revision 28 4. In the top picture (below), Kent Budgett is pulling upon a rope which is attached to a wall. In the bottom picture, the Kent is pulling upon a rope which is attached to an elephant. In each case, the force scale reads 500 Newtons. Kent is pulling... A. with more force when the rope is attached to the wall. B. with more force when the rope is attached to the elephant. C. the same force in each case. Answer: C P3.4A Predict the change in motion of an object acted on by several forces. L3 1. The frog leaps from its resting position at the lake’s bank onto a lily pad. If the frog has a mass of 0.5 kg and the acceleration of the leap is 3 m/s 2, what is the force the frog exerts on the lake’s bank when leaping? A. B. C. D. 0.2 N 0.8 N 1.5 N 6.0 N Answer: C 2. Forces act on an object on a hill as shown in the diagram. What conclusion can be made about the objects motion? A. The object is motionless because the forces are balanced. B. The object will accelerate down the hill because there is insufficient friction. C. The object will accelerate up the hill due to the force pulling on it that direction. D. The diagram is too inconclusive to draw any conclusions from. Answer: A Physics Assessments – August 2008 Revision 29 3. A box is at rest on a hill. What is the correct vector diagram? A. B. C. D. Answer: C 4. If the forces acting upon an object are balanced, then the object A. B. C. D. must not be moving. must be moving with a constant velocity. must not be accelerating. none of these Answer: A P3.4B Identify forces acting on objects moving with constant velocity (e.g., cars on a highway). L1 P3.4C Solve problems involving force, mass, and acceleration in linear motion (Newton’s second law). L2 1. What is the mass of an object weighing 63 N on Earth? A. B. C. D. 0.1 kg 6.3 kg 73 kg 617 kg Answer: B Physics Assessments – August 2008 Revision 30 2. The frog leaps from its resting position at the lake’s bank onto a lily pad. If the frog has a mass of 0.5 kg and the acceleration of the leap is 3 m/s 2, what is the force the frog exerts on the lake’s bank when leaping? A. B. C. D. 0.2 N 0.8 N 1.5 N 6.0 N Answer: C Jesse records the following data during an experiment. Acceleration (m/s2) 3 Force (N) 9 5 15 6 18 11 33 3. According to Jesse’s experiment, which of the following best represents the relationship between force and acceleration? (k is a constant) A. F = k ‡ a B. F = k ‡ a2 C. F = D. F = Answer: A 4. According to the data, what would be the correct value of k? (ignore units) A. B. C. D. E. 6 5 4 3 2 Answer: D Physics Assessments – August 2008 Revision 31 5. A mother pushes her 120-newton child, who is sitting on a swing. If the mother exerts a 10newton force on the child for 0.50 second, what is the magnitude of the impulse imparted to the child by the mother? A. B. C. D. 5.0 N•s 20. N/s 60. N•s 240 N/s Answer: A 6. The diagram below shows a 2.0-kilogram block being moved across a frictionless surface by a 6.0-newton horizontal force. What is the magnitude of the acceleration of the block? A. B. C. D. 0.33 m/s2 6.0 m/s2 3.0 m/s2 12 m/s2 Answer: C 7. Each figure below shows a force measured in newtons pushing on a block. If there are no other forces pushing on the block, in which case is the acceleration of the block the greatest? A. B. C. D. Answer: C Physics Assessments – August 2008 Revision 32 8. In the diagram below, the upward drag force acting on a parachute is equal in magnitude but opposite in direction to the weight of the parachutist and equipment. As a result of the forces shown, the parachutist may be moving A. B. C. D. downward with decreasing speed downward at constant speed upward with decreasing speed upward with constant acceleration Answer: B P3.6C Explain how your weight on Earth could be different from your weight on another planet. L2 1. The magnitude of the acceleration due to gravity on the surface of planet A is twice as great as on the surface of planet B. What is the ratio of the weight of mass X on surface of planet A to its weight on the surface of planet B? A. B. C. D. 1:2 2:1 1:4 4:1 Answer: B 2. If an astronaut took a rocket ship to Mars what would change? A. B. C. D. Width of astronaut. Mass of astronaut. Height of astronaut. Weight of astronaut. Answer: D Physics Assessments – August 2008 Revision 33 3. When comparing mass and size data for the planets Earth and Jupiter, it is observed that Jupiter is about 300 times more massive than Earth. One might quickly conclude that an object on the surface of Jupiter would weigh 300 times more than on the surface of the Earth. For instance, one might expect a person who weights 500 N on Earth would weigh 150000 N on the surface of Jupiter. Yet this is not the case. In fact, a 500-N person on Earth weighs about 150 N on the surface of Jupiter. Explain how this can be. A. The affect of the greater mass of Jupiter is partly offset by the fact that the radius of Jupiter is larger. B. An object on Jupiter's surface is 10 times farther from Jupiter's center than it would be if on Earth's surface C. Jupiter’s density is less than Earth D. A and B Answer: D 4. How much would you weigh if you lived on a different planet? Planet Mercury Venus Earth Mars Jupiter Saturn Uranus Neptune Pluto Weight Earth weight Earth weight Earth weight Earth weight Earth weight Earth weight Earth weight Earth weight Earth weight Multiplier Factor 0.38 0.91 1.00 0.38 2.60 1.10 0.90 1.20 0.08 Paul weighs 200 pounds (lbs.). What will his weight be if he stands on the surface of Venus? A. B. C. D. 45 lbs 182 lbs 220 lbs 200 lbs. Answer: B Physics Assessments – August 2008 Revision 34 QUARTER TWO Unit Three P2.2g Apply the independence of the vertical and horizontal initial velocities to solve projectile motion problems. L2 1. A ball is thrown horizontally from the top of a building with an initial velocity of 15 meters per second. At the same instant, a second ball is dropped from the top of the building. The two balls have the same A. B. C. D. path as they fall final velocity as they reach the ground initial horizontal velocity initial vertical velocity Answer: D 2. A package falls out of a helicopter that is traveling horizontally at 70m/s. It falls into the water below 8.0 seconds later. Assuming no air resistance, what is the horizontal distance it travels while falling? A. B. C. D. 720 m 9m 560 m 114 m Answer: C 3. A projectile is fired horizontally in a vacuum. The projectile maintains its horizontal component of speed because it A. B. C. D. E. has no vertical component of speed to begin with Is not acted on by any forces. The net force acting on it is zeron. is not acted on by any horizontal forces. None of the above Answer: D 4. In the absence of air friction, the vertical component of a projectile’s velocity doesn’t change as the projectile moves. A. Always false B. always truce C. Sometimes true Answer: B Physics Assessments – August 2008 Revision 35 5. The horizontal component of a projectile’s velocity is independent of A. the range of the projectile B. time C. the vertical component of its velocity. Answer: C P3.4e Solve problems involving force, mass, and acceleration in two-dimensional projectile motion restricted to an initial horizontal velocity with no initial vertical velocity (e.g., a ball rolling off a table). L2 Aristotle developed a system of physics based on what he thought occurred in nature. For example, he thought that if a stone is released from rest, it instantaneously reaches a speed that remains constant as the stone falls, He also believed that the speed attained by a stone falling in air varies directly with the weight of the stone. A 5-pound stone, for example, falls with a constant speed 5 times as great as that of a 1-pound stone. Aristotle also noted that stones dropped into water continue to fall, but at a slower rate than stones falling through air. To account for this, he explained that the resistance of the medium through which an object falls also affects the speed. Therefore, he said, the speed of a falling object also varies inversely with the resistance of the medium, and this resistance is the same for all objects. Galileo disagreed with Aristotle’s explanation. HE generated the following arguments to refute Aristotle. Consider a stake partially driven into the ground and a heavy stone falling from various heights onto the stake. If the stone falls from a height of 1 cubit, the stake will be driven in a much smaller amount. Certainly, Galileo argued, if the stone is raised above the stake by only the thickness of a leaf, then the effect of the stone’s falling on the stake will be altogether unnoticeable. On the basis of a careful set of experiments, Galileo argued that the speed of an object released from rest varies directly with the time of fall. Also, the distance the object falls varies directly with the square of the time of fall if the effect of air resistance on the object is negligible. Thus, according to Galileo, objects actually fall with constant acceleration, and if air resistance is negligible, all objects have exactly the same acceleration. 1. A book dropped from a height of 1 meter falls to the floor in t seconds. To be consistent with Aristotle's views, from what height, in meters, should a book 3 times as heavy be dropped so that it will fall to the floor in the same amount of time? A. B. C. D. 1/9 1/3 1 3 Answer: D Physics Assessments – August 2008 Revision 36 2. Suppose a heavy object falls to the ground in t seconds when dropped from shoulder height. According to Galileo, if air resistance were negligible, how many seconds would it take an object half as heavy to fall to the ground from the same height? A. B. C. D. 0.5t 1.0t 1.5t 2.0t Answer: A 3. A piece of putty weighing 2 pounds is dropped down a shaft from the top of a tall building; 1 second later, a 3 pound piece of putty is dropped down the shaft. According to Aristotle, what happens to the 2 pieces of putty if they fall for a relatively long time? A. B. C. D. the 3 pound piece falls faster The 2 pound piece falls faster They fall at the same rate None of the above Answer: A P3.3d Calculate all the forces on an object on an inclined plane and describe the object’s motion based on the forces using free-body diagrams. L2 1. Little Johnny stands at the bottom of the driveway and kicks a soccer ball. The ball rolls northward up the driveway and then rolls back to Johnny. Which one of the following velocity-time graphs (A, B, C, or D) most accurately portrays the motion of the ball as it rolls up the driveway and back down? A. B. C. D. Graph A Graph B Graph C Graph D Answer: D Physics Assessments – August 2008 Revision 37 2. A golf ball is rolling across a horizontal section of the green on the 18th hole. It then encounters a steep downward incline (see diagram). Friction is involved. Which of the following ticker tape patterns (A, B, or C) might be an appropriate representation of the ball's motion? Answer: B 3. Missy dePenn’s eighth frame in the Wednesday night bowling league was a disaster. The ball rolled off the lane, passed through the freight door in the building’s rear, and then down the driveway. Millie Meater (Missy’s teammate), who was spending every free moment studying for her physics test, began visualizing the velocity-time graph for the ball’s motion. Which one of the velocity-time graphs (A, B, C, or D) would be an appropriate representation of the ball's motion as it rolls across the horizontal surface and then down the incline? Consider frictional forces. A. B. C. D. Graph A Graph B Graph C Graph D Answer: D 4. Three lab partners - Olive N. Glenveau, Glen Brook, and Warren Peace - are discussing an incline problem (see diagram). They are debating the value of the normal force. Olive claims that the normal force is 250 N; Glen claims that the normal force is 433 N; and Warren claims that the normal force is 500 N. While all three answers seem reasonable, only one is correct A. B. C. D. Olive is correct Warren is correct Glen is correct All are correct Answer: C Physics Assessments – August 2008 Revision 38 Unit Four P3.4f Calculate the changes in velocity of a thrown or hit object during and after the time it is acted on by the force. L2 P3.4g Explain how the time of impact can affect the net force (e.g., air bags in cars, catching a ball). L2 http://www.glenbrook.k12.il.us/GBSSCI/PHYS/Class/momentum/u4l2b.html P3.5a Apply conservation of momentum to solve simple collision problems. L2 1. The diagrams below show a cart moving with a velocity, V, on a frictionless surface as a wooden block is being dropped. The block then falls straight down onto the moving cart. Which of the following statements describes what will happen after the block lands on the moving cart? A. The cart will move to the left at a velocity less than the original velocity of the cart. B. The cart will move to the left at a velocity greater than the original velocity of the cart. C. The cart will move to the right at a velocity less than the original velocity of the cart. D. The cart will move to the right at a velocity greater than the original velocity of the cart. Answer: C 2. A cart at the top of a hill is released and rolls down the hill. Which of the following describes the energy of the cart just as it reaches the bottom of the hill? A. B. C. D. The cart has no energy. The cart has maximum kinetic energy The cart has maximum gravitational potential energy. The cart has equal gravitational potential and kinetic energy. Answer: B Physics Assessments – August 2008 Revision 39 3. A ball moving at 30 m/s has a momentum of 15 kg·m/s. The mass of the ball is — A. B. C. D. 45 kg 15 kg 2.0 kg 0.5 kg Answer: D P3.3b Predict how the change in velocity of a small mass compares to the change in velocity of a large mass when the objects interact (e.g., collide). L3 P3.3c Explain the recoil of a projectile launcher in terms of forces and masses. L2 P3.3d Analyze why seat belts may be more important in autos than in buses. L2 1. An upward force of 150 N is applied to a box weighing 70 N. Which of the following is the free-body force diagram for this situation? A. 70 N C. 80 N 220 N 150 N B. 80 N D. 150 N 70 N 70 N Answer: D Physics Assessments – August 2008 Revision 40 Unit Five P2.1E Describe and classify various motions in a plane as one dimensional, two dimensional, circular, or periodic. L2 P2.1F Distinguish between rotation and revolution and describe and contrast the two speeds of an object like the Earth. L2 P2.1h Identify the changes in speed and direction in everyday examples of circular (rotation and revolution), periodic, and projectile motions. L2 1. A roller coaster cart starts from rest and accelerates, due to gravity, down a track. The cart starts at a height that enables it to complete a loop in the track. [Neglect friction.] Which diagram best represents the path followed by an object that falls off the cart when the cart is at point D? A. B. C. D. Answer: A P2.2D State that uniform circular motion involves acceleration without a change in speed. L1 P2.2f Describe the relationship between changes in position, velocity, and acceleration during periodic motion. L2 Physics Assessments – August 2008 Revision 41 P3.4D Identify the force(s) acting on objects moving with uniform circular motion (e.g., a car on a circular track, satellites in orbit). L1 1. A small block of wood attached to a string is being spun around in a circle. Which diagram illustrates the direction of the centripetal force acting on the block? A. B. C. D. Answer: B 2. A roller coaster cart starts from rest and accelerators, due to gravity, down a track. The cart starts at a height that enables it to complete a loop in the track. [Neglect friction.] The magnitude of the centripetal force keeping the cart in circular motion would be greatest at point A. B. C. D. A B C D Answer: A Physics Assessments – August 2008 Revision 42 P3.6A Explain earth-moon interactions (orbital motion) in terms of forces. L2 1. A popular ride at the local amusement park is the log flume. In this ride the rider is placed in a boat designed to resemble a large log. The log with riders is moved along a water way until it is taken to the top of an incline. From the top of the incline the log is released. At the bottom of the incline the log returns to the water way from which the ride originated. Answer the following questions. a. What is the purpose of the water at the bottom of the flume? (Other than to float the boat.) b. Describe the forces the participant will feel at each of the labeled points (A through F) as he/she moves around the course, up the incline, down the incline and finally stops at the bottom. Answers: 1. The water absorbs the kinetic energy of the boat and provides a safe stop. (1 point) 2. Forces felt: A: Starting out from rest, small accelerating force. (1 point) B: Moving around curves, small centripetal force. (1 point) C: Starting up the incline, small accelerating force. (1 point) D: Dropping down the incline, accelerating force due to gravity. (1 point) E: Stopping at the bottom, large decelerating force. (1 point) Physics Assessments – August 2008 Revision 43 P3.6B Predict how the gravitational force between objects changes when the distance between them changes. L3 1. In order for the force to be 1N what would the distance for these objects have to be? A. B. C. D. .001m .001mm 1.35x1011m 1.16x107m Answer: A 2. According to Newton’s law of universal gravitation, what will have a greater affect on the gravitational force? A. B. C. D. An increase in m1 A decrease in m2 An increase in d A decrease in G Answer: C 3. Gravitational force F exists between point objects A and B separated by distance R. If the mass of A is doubled and distance R is tripled, what is the new gravitational force between A and B? 2 F 9 2 B. F 3 3 C. F 2 9 D. F 2 A. Answer: A Physics Assessments – August 2008 Revision 44 P3.6d Calculate force, masses, or distance, given any three of these quantities, by applying the Law of Universal Gravitation, given the value of G. L2 1. What would be the force between A. B. C. D. the objects shown below? 5.9 x 10-9N 88.8N 7.99 x 1011N 9.8N Answer: A P3.6e Draw arrows (vectors) to represent how the direction and magnitude of a force changes on an object in an elliptical orbit. L2 Physics Assessments – August 2008 Revision 45 Unit Six P3.2B Compare work done in different situations. P4.1c Explain why work has a more precise scientific meaning than the meaning of work in everyday language. L2 P4.1d Calculate the amount of work done on an object that is moved from one position to another. L2 1. A 500.-newton girls lifts a 10.-newton box vertically upward a distance of 0.50 meter. The work done on the box is A. B. C. D. 5.0 J 50. J 250 J 2500 J Answer: C 2. The diagram below shows a 5.0-kilogram mass sliding 9.0 meters down an incline from a height of 2.0 meters in 3.0 seconds. The object gains 90. joules of kinetic energy while sliding. What work is done on the object? A. B. C. D. 0J 8J 45 J 90. J Answer: C 3. If a force of 100 newtons was exerted on an object and no work was done, the object must have — A. B. C. D. accelerated rapidly remained motionless decreased its velocity gained momentum Answer: B Physics Assessments – August 2008 Revision 46 4. How much work is performed when a 50 kg crate is pushed 15m with a force of 20 N? A. B. C. D. 300 J 750 J 1,000J 15,000 J Answer: A P4.1e Using the formula for work, derive a formula for change in potential energy of an object lifted a distance h. L3 P4.3A Identify the form of energy in given situations (e.g., moving objects, stretched springs, rocks on cliffs, energy in food). L1 1. What is the type and amount of energy in a wrecking ball weighing 100 pounds suspended 100 feet above the ground? A. B. C. D. E. Accumulative energy of 1,000 lbs/ft Floatational energy of 1,000 lbs Kinetic energy of 5,000 ft. lbs Potential energy of 10,000 ft. lbs Weight energy of 10,000 lbs Answer: D Physics Assessments – August 2008 Revision 47 Following are six examples of kinetic and potential energy. Carefully analyze each image in order to answer the following five questions. Pneumatic power wrench Electric-motor power saw Conveyor system Water tower Auto suspension spring and shock absorber Electric batteries 2. The water tower and batteries can be categorized with which other image representing potential energy? A. B. C. D. Pneumatic wrench Conveyor system Power saw Shock absorber Answer: D Physics Assessments – August 2008 Revision 48 3. If an electrical generating turbine were added to one of the examples, which form of potential energy might power the electric saw? A. B. C. D. E. The conveyor system The shock absorber The water tower The power wrench The batteries Answer: C 4. If an air compressor were attached to the power wrench, which of the following would occur? A. The potential energy in the compressor would all become kinetic energy in the wrench. B. The wrench would not be able to do as much work out as the work in from the compressor. C. The wrench will do more work than the compressor can input. D. The kinetic energy stored in the compressor will make the wrench work. Answer: B 5. How could you increase the potential energy of the water in the tower? A. B. C. D. Increase the height of the tower. Increase the pipe’s diameter. Increase the number of filters in the water tank. Increase the valve opening at the end of the pipe. Answer: A 6. What is the potential energy of the spring in the suspension system based on? A. B. C. D. E. The kinetic energy of the car The amount of air pressure in each tire The springs speed The spring height The spring constant Answer: E Physics Assessments – August 2008 Revision 49 P4.3B Describe the transformation between potential and kinetic energy in simple mechanical systems (e.g., pendulums, roller coasters, ski lifts). L2 P4.3C Explain why all mechanical systems require an external energy source to maintain their motion. L2 P43d Rank the amount of kinetic energy from highest to lowest of everyday examples of moving objects. L2 P4.3e Calculate the changes in kinetic and potential energy in simple mechanical systems (e.g., pendulums, roller coasters, ski lifts) using the formulas for kinetic energy and potential energy. L2. 1. What is the potential energy of the rock? A. B. C. D. 59,900 joules 64,600 joules 93,100 joules 121,600 joules Answer: C Physics Assessments – August 2008 Revision 50 Data showing typical ball speeds and striker speeds for different sports: Ball type Tennis ball Squash ball Hand ball Golf ball Football kick Cricket ball Ball mass (kg) 0.058 0.032 0.061 0.046 0.42 0.16 Ball velocity (m/s) before (m/s) after 0 51 0 49 0 23 0 69 0 28 0 39 Striker velocity (m/s) after (m/s) before 38 33 44 34 19 14 45 32 18 12 31 27 Impact time (ms) 4.0 3.0 1.4 8.0 8.0 1.4 (Data taken from : Physics, R. Hutchins, University of BATH, Thomas Nelson & Sons Ltd., 1992) 1. Find the kinetic energies of each ball just after it is struck. (12pts) 2. Find the loss in kinetic energy of the golf driver as it hits the golf ball. (2pts) Answer 1: Use K.E. = 1/2 mv2 75 J, 38 J, 16 J, 110 J, 165 J, 122 J (2pts each correct answer and set up) Answer 2: Use K.E. = 1/2 mv2 final - 1/2 mv2 initial K.E. = 122 J (1pt for answer and 1pt for set up) 3. An airplane drops 400 m to escape some freezing rain. If it maintained the same speed but lost 200,000,000 J of energy: A. B. C. D. Answers: A. B. C. D. How much PE did it lose? How much KE did it lose? What is the plane’s mass? Since the total energy of the system doesn’t seem to be conserved, explain where the 200,000,000 J went. 200,000,000 J 0J 51,000 kg Air friction Physics Assessments – August 2008 Revision 51 P4.3f Calculate the impact speed (ignoring air resistance) of an object dropped from a specific height or the maximum height reached by an object (ignoring air resistance), given the initial vertical velocity. L2 During an experiment a group of Physics students drop a 0.250 kg ball from a lab table. Using a Photogate timer for several readings they find that it took the ball an average of 0.306 seconds to hit the floor. 1. What is the velocity of the ball just before it hit the ground? (3 points) 2. Find the change in kinetic energy of the ball? (3 points) Answer 1: v=gt = (9.81 m/s2)(0.306 seconds) = 3.00 m/s (1 point for correct equation, 1 point for the correct answer, and 1 point for the correct units) Answer 2: KE = KE Æ KE ; 1.13 J (1 point for the equation, 1 point for the correct answer, and 1 point for the work energy equation) Physics Assessments – August 2008 Revision 52 Unit Seven P4.1A Account for and represent energy into and out of systems using energy transfer diagrams. L3 P4.2A Account for and represent energy transfer and transformation in complex processes (interactions). L3 1. The masses and specific heats of some samples of liquids are shown in the table below Samples Mass (kg) Specific Heat Capacity (J/kg · K) water 0.750 4200 glycerin 0.750 2400 methanol 0.750 2500 cooking oil 0.750 2100 The temperature of which sample will raise most when 1000 J of heat is added? A. B. C. D. water Glycerin methanol cooking oil Answer: D Physics Assessments – August 2008 Revision 53 P1.2C Develop an understanding of a scientific concept by accessing information from multiple sources. Evaluate the scientific accuracy and significance of the information 1. According to the information in Figure 3 above, the greatest heat gained through double-pane glass occurs in which of the following cities? A. B. C. D. Albuquerque Minneapolis New Orleans Phoenix Answer: A Physics Assessments – August 2008 Revision 54 2. According to the data, the greatest net heat loss through a single-pane window occurred in which city? A. B. C. D. Concord Huron Minneapolis Phoenix Answer: C 3. Indianapolis, Indiana, receives 51% possible sunshine and has an average temperature of 40.3°F during the heating season. On the basis of the data presented, the net heat gained by a double-pane window in Indianapolis would be approximately: A. B. C. D. –15 Btu/hr/ft2. 7 Btu/hr/ft2.11 11 Btu/hr/ft2. 27 Btu/hr/ft2. Answer: B 4. Which of the following hypotheses about the relationship between the percent of possible sunshine and average outdoor temperature during the heating season is best supported by the data? A. B. C. D. As the percent of possible sunshine increases, the average temperature decreases. As the percent of possible sunshine increases, the average temperature increases. The average temperature is not directly related to the percent of possible sunshine. The percent of possible sunshine depends on the length of the heating season, rather than the average temperature. Answer: C P4.2B Name devices that transform specific types of energy into other types (e.g., a device that transforms electricity into motion). L1 1. Household appliances convert electricity into one or more different forms of energy. An electric fan can best be described as converting electricity into A. B. C. D. heat energy only heat energy and sound energy only heat energy, sound energy, and mechanical energy only heat energy, sound energy, mechanical energy, and chemical energy Answer: C Physics Assessments – August 2008 Revision 55 P4.2C Explain how energy is conserved in common systems (e.g., light incident on a transparent material, light incident on a leaf, mechanical energy in a collision). L2 P4.2e Explain the energy transformation as an object (e.g., skydiver) falls at a steady velocity. L2 P4.2f Identify and label the energy inputs, transformations, and outputs using qualitative or quantitative representations in simple technological systems (e.g., toaster, motor, hair dryer) to show energy conservation. L2 P1.1B Evaluate the uncertainties or validity of scientific conclusions using an understanding of sources of measurement error, the challenges of controlling variables, accuracy of data analysis, logic of argument, logic of experimental design, and/or the dependence on underlying assumptions conservation. L2 Researchers conducted an experiment to determine the factors affecting heat flow. In each trial, one or more blocks of a particular material was (were) placed between two walls at constant temperatures T1 and T2 in one of the configurations show in Figure 1. Heat was transferred through the block(s) from the hotter wall to the cooler wall. This heat flow, measured in joules per second (J/sec), is shown in Table 1. (Note: All blocks used in the experiment were identical in size and shape. In each configuration, the contact area was the surface area of the end of the block(s) against one wall.) Physics Assessments – August 2008 Revision 56 1. According to the information provided, heat flowed from the wall at temperature T2 to the wall at temperature T1 in which trial? A. B. C. D. Trial 4 Trial 6 Trial 10 Trial 12 Answer: B 2. Insulators are materials that are poor heat conductors. According to Trials 7 through 10, a wall of a given thickness built of which of the following materials would provide the best insulation between a room and the outdoors? A. B. C. D. Wood Brick Concrete Steel Answer: A 3. The results of Trials 1 and 5 are consistent with the hypothesis that heat flow from a hotter wall to a cooler wall is dependent on the: A. temperature of the hotter wall only. B. temperature of the cooler wall only. C. sum of the wall temperatures. D. difference between the wall temperatures. Answer: D Physics Assessments – August 2008 Revision 57 4. Materials differ in their thermal conductivities: the higher the thermal conductivity, the greater the heat flow through the material. According to Trials 6 through 11, which of the following statements about relative thermal conductivities is NOT true? A. B. C. D. Brick has a higher thermal conductivity than glass wool. Brick has a higher thermal conductivity than wood Steel has a higher thermal conductivity than aluminum. Steel has a higher thermal conductivity than concrete. Answer: C 5. Trials 1 and 3 provide evidence that heat flow depends on which of the following factors? A. B. C. D. Distance between walls Contact area Temperature of the hotter wall Temperature of the cooler wall Answer: A Indicate whether each statement is an example or not of valid science affecting human life by circling “yes” for each example and “no” for each non-example. 1. 2. 3. Yes Yes Yes No No No 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes No No No No No No No No No No No No A car radiator removes heat from the engine. Scientists gather data about long-term weather patterns. Satellites in orbit transmit location coordinate signals to ground-based receivers. Copper bracelets are sold to relieve pain. Manufacturers produce more efficient batteries. Water filters that enhance water’s nutritional value. Physicists collide subatomic particles in a lab. Magnetic insoles in shoes improve your health. False colored contact lenses change eye-color. Materials engineers research stronger light-weight materials. Dams are used to produce electricity. Dams create lakes used for recreational activities. Homes have indoor plumbing. More powerful batteries keep getting smaller. Fluorescent lights produce the same light with less power. Physics Assessments – August 2008 Revision 58 Correct Answers: 1. Yes 2. Yes 3. Yes 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. No Yes No Yes No Yes Yes Yes Yes Yes Yes Yes A car radiator removes heat from the engine. Scientists gather data about long-term weather patterns. Satellites in orbit transmit location coordinate signals to ground-based receivers. Copper bracelets are sold to relieve pain. Manufacturers produce more efficient batteries. Water filters that enhance water’s nutritional value. Physicists collide subatomic particles in a lab. Magnetic insoles in shoes improve your health. False colored contact lenses change eye-color. Materials engineers research stronger light-weight materials. Dams are used to produce electricity. Dams create lakes used for recreational activities. Homes have indoor plumbing. More powerful batteries keep getting smaller. Fluorescent lights produce the same light with less power. 1. A building contractor was given several options as to the type of building materials he could use in a house he was constructing. He was told that he could use either pine or oak for trim, and concrete, cinder block or building block for walls. The buyers instructed the contractor to build the house as thermally efficient as feasible. Building block =3-6 Cinder block=2-3 Concrete=6-9 Glass=5-6 Oak=1.02 Pine=0.78 Using the above chart of thermal conductivity, what materials would he use? A. B. C. D. E. Building block and oak Building block and pine Cinder block and oak Cinder block and pine Concrete and oak Answer: D P4.11b Calculate the final temperature of two liquids (same or different materials) at the same or different temperatures and masses that are combined. L2 Physics Assessments – August 2008 Revision 59 THIRD QUARTER Unit Eight P4.4A Describe specific mechanical waves (e.g., on a demonstration spring, on the ocean) in terms of wavelength, amplitude, frequency, and speed. L2 1. The illustration below shows three toy ducks floating on water, moving up and down as a wave travels to the right with a velocity of 3 m/s. Which of the following is the frequency of the wave? A. B. C. D. 0.75 Hz 1.33 Hz 1.5 Hz 6.0 Hz Answer: A 2. The figure above shows some ocean waves. Which of the labeled distances represents the wavelength? A. B. C. D. A B C D Answer: A 3. A person produces two sound waves with a flute, one immediately after the other. Both sound waves have the same pitch, but the second one is louder. Which of the following properties is greater for the second sound wave? A. B. C. D. Frequency Amplitude Wavelength Speed in air Answer: B Physics Assessments – August 2008 Revision 60 4. The diagram below represents a periodic wave generated during a 1.5-second interval. The frequency of the wave is A. B. C. D. 1.0 Hz 2.0 Hz 0.50 Hz 4.5 Hz Answer: A 5. The __________ of a sound determines its loudness. A. B. C. D. amplitude resonance timbre frequency Answer: A 6. A water wave in a ripple tank is moving at a speed of 10 cm/s with a wavelength of 4.0 cm. It moves into a new area of the ripple tank where the wavelength of the wave is 3.2 cm. The speed of the water wave in the new area is A. B C. D. 12.5 cm/s 10 cm/s 8.0 cm/s 1.28 cm/s Answer: C 7. A sound wave travels at 343 m/s and a compression passes by every 12 ms. What is the wavelength of this sound? A. B. C. D. 1m 2m 3m 4m Answer: D Physics Assessments – August 2008 Revision 61 In an experiment, you adjust the frequency of a wave and measure the resulting wavelengths. You obtain the following data: Frequency, f (hz) 5 8 11 14 Wavelength, (m) 0.4 0.25 0.182 0.143 Wave speed, (m/s) 2.00 2.00 2.00 2.00 8. What statement best describes the relationship between the variables? A. Wavelength is proportional to frequency. B. Frequency is proportional to wave speed. C. Wave speed is proportional to wavelength. Answer: A 9. What statement best describes the relationship between the variables? A. Frequency and wavelength are directly proportional. B. Frequency and wavelength are not proportional. C. Frequency and wavelength are inversely proportional. Answers: C 10. In an experiment, you adjust the frequency of a wave and measure the resulting wavelengths. You obtain the following data: Frequency, f (hz) 5 8 11 14 Wavelength, (m) 0.4 0.25 0.182 0.143 What relationship is being studied? A. B. C. D. How frequency affects wave speed. How frequency affects wavelength. How wavelength affects frequency. How wavelength affects wave speed. Answer: B Physics Assessments – August 2008 Revision 62 Wave speed, (m/s) 2.00 2.00 2.00 2.00 11. Which is the independent variable? A. Frequency B. Wavelength C. Wave speed Answer: A 12. Which is the dependent variable? A. Frequency B. Wavelength C. Wave speed Answer: B 13. In an experiment, you adjust the frequency of a wave and measure the resulting wavelengths. You obtain the following data: Frequency, f (hz) 5 8 11 14 Wavelength, (m) 0.4 0.25 0.182 0.143 Wave speed, (m/s) 2.00 2.00 2.00 2.00 Which graph would be obtained from the data? A. B. C. D. E. Answer: E Physics Assessments – August 2008 Revision 63 Surfer dude (a non-scientist) found some nice waves while on a hike to an unfamiliar part of the coastal area. He visited this site many times during the next few days and recorded his observations. He even timed the waves and recorded their periodicity. Remembering the equation for frequency from his high school physics class he even calculated the frequency of the waves. That weekend he exclaimed to his buddies that he had found a great place to try surfing and stated how many waves could be expected per hour. 14. What would be the wisest reaction by his buddies? A. B. C. D. Dismiss his claims; they sound too good. Go check it out since even surfer dude can do good science. Don’t believe a word he says since only a real scientist could know this. Get a scientist to prove his claims true or false. Answers: B Physics Assessments – August 2008 Revision 64 Slinky Waves Materials: slinky or long spring meter stick Polaroid camera stopwatch Procedure: 1. Place a slinky on a table. Hold one end fixed while generating a single transverse pulse at the other end. Sketch the shape of the generated pulse and of the reflected pulse. 2. Produce both the transverse and the longitudinal pulses in the slinky and describe the differences. (Notice the speed difference). 3. Generate a transverse periodic wave in the slinky, and determine its wavelength, (Place a meter stick near the slinky and take a picture). W=__________ 4. Use a stopwatch to determine the period (T) of the wave. T=__________ 5. Calculate the velocity of the wave. 6. Adjust the frequency of the periodic waves until a standing-wave pattern is observed. Draw a sketch of the standing wave pattern. Answers: 1. (2pts) The sketch should show a single crest going into the fixed point, and a crest going out of the fixed point but on the other side. The crest will invert when reflected. 2. (2pts) In the longitudinal wave motion, the vibration is parallel to the direction of the energy propagation. It is also faster than the transverse wave. (2pts) In the transverse wave, the vibration is perpendicular to the direction of propagation of energy. It is also slower than the longitudinal wave. 3. Answer varies = __________ (2pts) 4. Answer varies T = __________ (2pts) 5. Answer varies, however the students should have used the following equation: v = / T (2pts) 6. The sketch should look like the sine wave (2pts) Physics Assessments – August 2008 Revision 65 15. A ray of light strikes a swimming pool at an angle of 32 degrees with the normal. Find the index of refraction of the pool if the angle of refraction is 25 degrees. Show your work. Answer: 1.25 16. The index of refraction of diamond is 2.42. What is the speed of light in diamond? Show your work. Answer: 1.24 x 108 m/s 17. The whistle on a train has a frequency of 440 Hz. The train is moving at 35.0 m/s toward a person standing beside the tracks. If sound travels at 345 m/s, what is the wavelength of the sound heard by the person? Answer: 0.70 m 18. A police car with a siren having a frequency of 365 Hz is approaching a stationary observer at a speed of 75 km/h. What will the frequency of the siren appear to be if sound travels at 345 m/s? Answer: 388 Hz P4.4B Identify everyday examples of transverse and compression (longitudinal) waves. L1 1. Bats use high frequency sound waves to locate their prey and to navigate in the dark. As sound waves reflect off an object and back to the bat’s ears, the bat is able to determine the precise location of the prey. Which technological advance was aided by studying how bats locate objects using sound waves? A. B. C. D. 3-D computer modeling sonar navigation for submarines X-rays for analyzing body structures night-vision goggles for military operations Answer: B Physics Assessments – August 2008 Revision 66 P4.4C Compare and contrast transverse and compression (longitudinal) waves in terms of wavelength, amplitude, and frequency. L2 1. Which of the following statements is true about the waves in the diagram below? A. B. C. D. Wave B has a higher frequency than Wave A. Wave A has a higher density than Wave B. Wave A has a greater amplitude than Wave B. Wave B has a longer wavelength than Wave A. Answer: A P4.4d Demonstrate that frequency and wavelength of a wave are inversely proportional in a given medium. 1. A radio transmitter broadcasts a signal at a given frequency. If the broadcast frequency is increased, what happens to the speed and the wavelength of the radio waves? A. B. C. D. Speed Increases Increases Remains the same Remains the same Wavelength Decreases Increases Decreases Increases Answer: C 2. In the Doppler Effect, light reaching the Earth from a distant galaxy in an expanding universe is shifted to A. B. C. D. longer wavelengths higher frequencies greater velocities greater amplitudes Answer: A Physics Assessments – August 2008 Revision 67 P4.4e Calculate the amount of energy transferred by transverse or compression waves of different amplitudes and frequencies (e.g., seismic waves). L2 1. What is the velocity of a wave if its frequency is 250 Hz, its wavelength is 20.0 m, and its amplitude is 0.150 m? A. B. C. D. 37.5 m/s 0.080 m/s 1667 m/s 5000 m/s Answer: D P4.5A Identify everyday examples of energy transfer by waves and their sources. L1 1. Which of the following terms can be used to describe sound waves but NOT light waves? A. B. C. D. electromagnetic mechanical transverse concentric Answer: B 2. One tuning fork is struck and placed next to an identical fork. The two forks do not touch. The second tuning fork starts to vibrate because of — A. B. C. D. interference the Doppler Effect resonance standing waves Answer: C P4.5B Explain why an object (e.g., fishing bobber) does not move forward as a wave passes under it. L2 Physics Assessments – August 2008 Revision 68 P1.1h Design and Conduct a systematic scientific investigation that tests a hypothesis. 1. Oil is spilled onto the water from an oceangoing tanker. Investigators want to know whether wave motion will help disperse the oil. Design an experiment that they can carry out in a laboratory to find out whether wave motion will help disperse the oil. Describe the equipment they should use and the procedure they should follow. Equipment: Procedure: P4.5C Provide evidence to support the claim that sound is energy transferred by a wave, not energy transferred by particles. L2/3 1. If a ringing bell is placed in a vacuum chamber and all of the air is removed, what will happen? A. B. C. D. The bell will make no sound. The sound will shatter the vacuum chamber. The ringing will become quieter. The ringing will become louder. Answer: A Physics Assessments – August 2008 Revision 69 2. If a television is placed in a vacuum chamber and all of the air is removed, what will happen? A. B. C. D. You would be able to see the light from the screen and the sound would be louder. You would be able to see the light from the screen, but you would hear no sound. You would not be able to see the light from the screen or hear any sound. The light from the screen would be dimmer and the sound would be quieter. Answer: B P4.5D Explain how waves propagate from vibrating sources and why the intensity decreases with the square of the distance from a point source. L2 1. A sound wave is traveling through a bucket of water. Which of the following would cause the sound wave to slow down? A. B. C. D. increasing the amplitude of the sound wave changing the water from a liquid to a gas increasing the wavelength of the sound wave changing the water from a liquid to a solid Answer: B P4.5E Explain why everyone in a classroom can hear one person speaking, but why an amplification system is often used in the rear of a large concert auditorium. Physics Assessments – August 2008 Revision 70 P4.8c Describe how two wave pulses propagated from opposite ends of a demonstration spring interact as they meet. L2 1. Which diagram correctly illustrates diffraction of light? A. B. C. D. Answer: A P4.8d List and analyze everyday examples that demonstrate the interference characteristics of waves (e.g., dead spots in an auditorium, whispering galleries, colors in a CD, beetle wings). L2 1. Which of the following wave interactions will result in constructive interference? A. B. C. D. Answer: A Physics Assessments – August 2008 Revision 71 2. Which of the following may be the result if sound waves undergo constructive interference? A. B. C. D. decreased amplitude decreased frequency increased wavelength increased amplitude Answer: D 3. Which of the following occurs as a result of constructive interference? A. B. C. D. a wave that has a smaller amplitude a wave that has a larger amplitude a wave that has a larger wavelength a wave that has a smaller wavelength Answer: B 4. Which of the following diagrams correctly shows constructive interference? A. B. C. D. Answer: D Physics Assessments – August 2008 Revision 72 5. Which of the following wave interactions would create "noise"? A. B. C. D. Answer: C 6. At which point will destructive interference occur on the concentric waves below? A. B. C. D. 4 3 1 2 Answer: A Physics Assessments – August 2008 Revision 73 Unit Nine P3.1b Explain why scientists can ignore the gravitational force when measuring the net force between two electrons. L2 P3.1c Provide examples that illustrate the importance of the electric force in everyday life. L2 P3.7A Predict how the electric force between charged objects varies when the distance between them and/or the magnitude of charges change. L3 1. The diagram below shows two negatively charged balloons suspended from nonconducting strings being held by a student. What occurs as the student brings the balloons closer to each other without allowing them to touch? A. The magnitude of the electrostatic force between the balloons decreases, and they attract each other. B. The magnitude of the electrostatic force between the balloons decreases, and they repel each other. C. The magnitude of the electrostatic force between the balloons increases, and they attract each other. D. The magnitude of the electrostatic force between the balloons increases, and they repel each other Answer: D P3.7B Explain why acquiring a large excess static charge (e.g., pulling off a wool cap, touching a Van de Graaff generator, combing) affects your hair. L2 Physics Assessments – August 2008 Revision 74 P3.7c Draw the redistribution of electric charges on a neutral object when a charged object is brought near. L3 1. Two electrically neutral metal spheres, A and B, on insulating stands are placed in contact with each other. A negatively charged rod is brought near, but does not touch the spheres, as shown in the diagram below. How are the spheres now charged? A. B. C. D. A is positive and B is positive A is positive and B is negative A is negative and B is positive A is negative and B is negative Answer: B P3.7d Identify examples of induced static charges. L1 P3.7e Explain why an attractive force results from bringing a charged object near a neutral object. L2 1. The force between two static charges is +4N. The force is: A. repulsive B. attractive C. can't tell Answer: A 2. In a professional automobile paint shop, an electric charge is created on the surface of the automobile, and an electric charge is created on the tiny paint particles that are to be applied. This will help create a better paint job on the automobile. Using what you understand about electric charges, which of the following best explains why this would be done? A. B. C. D. The two electric charges are the same so the paint will be attracted to the car. The two electric charges are different so the paint will be attracted to the car. The two electric charges are the same so the paint will be repelled from the car. The two electric charges are different so the paint will be repelled from the car. Answer: B Physics Assessments – August 2008 Revision 75 3. Joell rubbed a plastic pen with a piece of paper towel to charge it, then held the pen next to a small stream of water from the faucet. Which illustration correctly shows the effect the charged pen had on the water? A. B. C. D. Answer: D P3.7f Determine the new electric force on charged objects after they touch and are then separated. L2 1. At point P in an electric field, the magnitude of the electrostatic force on a proton is 4.0 x 10-10 newton. What is the magnitude of the electric field intensity at point P? A. B. C. D. 6.4 x 10-29 N/C 1.6 x 10-19 N/C 4.0 x 10-10 N/C 2.5 x 109 N/C Answer: C P3.7g Propose a mechanism based on electric forces to explain current flow in an electric circuit. L3 P3.8b Explain how the interaction of electric and magnetic forces is the basis for electric motors, generators, and the production of electromagnetic waves. L2 Physics Assessments – August 2008 Revision 76 Unit Ten P4.10A Describe the energy transformations when electrical energy is produced and transferred to homes and businesses. L2 Much of the electricity in Utah comes from hydroelectric power plants, which are components of many dams. Trace electrical energy from this source to an electrical appliance in your house. Possible Answer: Hydroelectric power is produced from water moving through a dam. Water flowing through the dam converts potential mechanical energy to kinetic mechanical energy. This kinetic energy turns a turbine in the dam, which is connected to the shaft of a generator. The generator takes the mechanical energy and converts it to electrical energy. It is then sent through power lines and a transformer (which converts electricity into a usable voltage) to your house. There it is converted into useful energy by your home appliances. Scoring Guide: Conversion of potential to kinetic energy Kinetic energy turns turbine in generator Generator changes mechanical energy to electrical energy Electrical energy travels through power lines Correct spelling, punctuation and language use 30% 10% 30% 10% 20% P4.10B Identify common household devices that transform electrical energy to other forms of energy, and describe the type of energy transformation. L1 & L2 Match and classify the following energy transformations with the most relevant energy converter. ___1. Electrical energy to thermal energy ___2. Thermal energy to fluid energy ___3. Solar energy to thermal energy ___4. Fluid energy to mechanical energy ___5. Electrical energy to mechanical energy ___6. Mechanical energy to fluid energy ___7. Mechanical energy to electrical energy. a. Motor b. Generator c. Windmill d. Steam Generator e. Solar Collector f. Heating Device g. Pump Fan h. Car Engine i. Bicycle Answers: 1. f 2. d 3. e 4. c 5. a 6. g 7. b Physics Assessments – August 2008 Revision 77 P4.10C Given diagrams of many different possible connections of electric circuit elements, identify complete circuits, open circuits, and short circuits and explain the reasons for the classification. L2 1. Fill in the blanks. When the switch in a circuit is _______________ , the circuit is _______________ . A. B. C. D. open; parallel closed; complete open; complete closed; parallel Answer: B 2. Which of these circuits is complete? A. B. C. D. Answer: A Physics Assessments – August 2008 Revision 78 3. Look at the diagram and then fill in the blank. This circuit is _______________. A. B. C. D. complete closed on open Answer: D P4.10D Discriminate between voltage, resistance, and current as they apply to an electric circuit. L2 P4.10e Explain energy transfer in a circuit, using an electrical charge model. L2 1. What would be the result if the voltage in a circuit is increased and the resistance is decreased? A. B. C. D. The current would remain constant. The current would increase. The current would decrease. There is not enough information Answer: B 2. What would be the result if the current and the resistance in a circuit are decreased? A. B. C. D. The voltage would remain constant The voltage would increase. There is not enough information. The voltage would decrease. Answer: D 3. What would be the result if the voltage in a circuit is decreased and the resistance remains constant? A. B. C. D. There is not enough information. The current would stay the same. The current would decrease. The current would increase. Answer: C Physics Assessments – August 2008 Revision 79 4. Which of the following statements would be true of the voltage in a circuit if the current is increased, but the resistance remains constant? A. B. C. D. The voltage would increase. The voltage would decrease. There is not enough information. The voltage would remain constant. Answer: A P4.10f Calculate the amount of work done when a charge moves through a potential difference, V. L2 1. An electric circuit is shown below. The accompanying table shows the current measured at different levels of resistance. Based on the data shown in the table, what is the voltage drop across the variable resistor? A. B. C. D. 1.5 V 6V 9V 12 V Answer: A 2. A light bulb connected to a 12 V battery carries a current of 5.0 A. What is the power of the light bulb? A. B. C. D. 0.41 W 60 W 2.4 W 100 W Answer: B Physics Assessments – August 2008 Revision 80 3. If 1.0 joule of work is required to move a charge of 1.0 coulomb between to points in an electric field, the potential difference between these two points is A. B. C. D. 1.0 V 1.6 x 10-19 V 9.0 x 109 V 6.3 x 1018 V Answer: A P4.10g Compare the currents, voltages, and power in parallel and series circuits. L2 1. A microwave oven operating at 120 volts is used to heat a hot dog. If the oven draws 12.5 amperes of current for 45 seconds, what is the power dissipated by the oven? A. B. C. D. 33 W 1.5 x 103 W 5.4 x 103 W 6.8 x 104 W Answer: A P4.10h Explain how circuit breakers and fuses protect household appliances. L2 Electric shocks can be very dangerous to humans. Describe two ways of avoiding electric shocks in the home. P4.10i Compare the energy used in one day by common household appliances (e.g., refrigerator, lamps, hair dryer, toaster, televisions, music players). L2 1. For which quantities are values needed to calculate the amount of energy supplied to an operating toaster? A. B. C. D. applied voltage and resistance, only applied voltage and operation time, only applied voltage, current drawn, and resistance applied voltage, current drawn, and operation time Answer: D P4.10j Explain the difference between electric power and electric energy as used in bills from an electric company. L2 Physics Assessments – August 2008 Revision 81 QUARTER FOUR Unit Eleven P4.6A Identify the different regions on the electromagnetic spectrum and compare them in terms of wavelength, frequency, and energy. L1 & L2 1. When the prism below captures light and creates a rainbow, why is red the color on top of the rainbow? A. B. C. D. Red has the shortest wavelength so it refracts the most in the prism. Red has the longest wavelength so it refracts the least in the prism. Red is the brightest color so it exits the prism the fastest. Red is the brightest color so it exits the prism the slowest. Answer: B 2. The wavelength of green light is about 500 nm. Which of the following could be the wavelength of blue light? A. B. C. D. 0 nm 1000 nm 550 nm 450 nm Answer: D 3. The wavelength of violet light is 400 nm. What would you expect the wavelength of yellow light to be? A. 300 nm B. The wavelengths would be equal. C. 600 nm D. 200 nm Answer: C Physics Assessments – August 2008 Revision 82 4. Use the diagram below to answer the question. Which number indicates the X-ray portion of the electromagnetic spectrum? A. B. C. D. 4 2 1 3 Answer: A 5. Which of the following parts of the electromagnetic spectrum has the shortest wavelength? A. B. C. D. violet red infrared microwaves Answer: A 6. Which waves are parts of the electromagnetic spectrum? A. B. C. D. radio waves seismic waves transverse waves mechanical waves Answer: A 7. Use the diagram below to answer the question. Which type of wave would be found between numbers 3 and 4 on the electromagnetic spectrum? A. B. C. D. radio ultraviolet microwave infrared Answer: B Physics Assessments – August 2008 Revision 83 8. Which of the following parts of the electromagnetic spectrum has the least amount of energy? A. B. C. D. infrared waves radio waves visible light ultraviolet waves Answer: B 9. The figure below shows the regions of the electromagnetic spectrum. Which of the following statements best compares the wavelengths of the regions of the electromagnetic spectrum? A. B. C. D. Microwaves are shorter than x-rays. Infrared waves are longer than gamma rays. Radio waves are shorter than visible light waves. Ultraviolet waves are longer than visible light waves Answer: B P4.6B Explain why radio waves can travel through space, but sound waves cannot. L2 1. If a ringing bell is placed in a vacuum chamber and all of the air is removed, what will happen? A. B. C. D. The bell will make no sound. The sound will shatter the vacuum chamber. The ringing will become quieter. The ringing will become louder. Answer: A 2. If a television is placed in a vacuum chamber and all of the air is removed, what will happen? A. B. C. D. You would be able to see the light from the screen and the sound would be louder. You would be able to see the light from the screen, but you would hear no sound. You would not be able to see the light from the screen or hear any sound. The light from the screen would be dimmer and the sound would be quieter. Answer: B Physics Assessments – August 2008 Revision 84 3. Two astronauts were conducting an experiment in space, where there is no air. Astronaut A was holding a radio that had the volume turned all the way up and a flashlight that was shining. Astronaut B was approximately 10 meters away facing the flashlight and radio. What did the astronauts probably discover? A. Neither astronaut A nor astronaut B could see the light from the flashlight or hear the radio. B. Both astronaut A and astronaut B could see the light from the flashlight, but only astronaut A could hear the radio. C. Both astronaut A and astronaut B could see the light from the flashlight, but neither astronaut could hear the radio. D. Astronaut A could see the light from the flashlight and hear the radio, but astronaut B could not. Answer: C 4. In space, an astronaut is able to see the light from stars but when he claps his hands, he cannot hear the sound. Why is this true? A. Light can travel infinitely, but sound can only travel a short distance. B. Sound can only be heard when there is gravity, and there is no gravity in space. C. Stars emit a great deal of light, so it is easy to see, but the sound must be very loud for him to be able to hear it. D. Sounds waves cannot travel in space, but electromagnetic waves can. Answer: D P4.6C Explain why there is a time delay between the times we send a radio message to astronauts on the moon and when they receive it. L2 P4.6D Explain why we see a distant event before we hear it (e.g., lightning before thunder, exploding fireworks before the boom). L2 Physics Assessments – August 2008 Revision 85 P4.6e Explain why antennas are needed for radio, television, and cell phone transmission and reception. L2 P4.6f Explain how radio waves are modified to send information in radio and television programs, radio-control cars, cell phone conversations, and GPS systems. L2 P4.6g Explain how different electromagnetic signals (e.g., radio station broadcasts or cell phone conversations) can take place without interfering with each other. L2 P4.6h Explain the relationship between the frequency of an electromagnetic wave and its technological uses. L2 P4.8A Draw ray diagrams to indicate how light reflects off objects or refracts into transparent media. L2 1. A candle is placed in front of a concave (diverging) lens at a distance greater than the focal length. Which of the following correctly diagrams this situation? A. C. B. D. Answer: A Physics Assessments – August 2008 Revision 86 2. An object is placed in front of a convex (converging) lens at a distance longer than the focal length. Which of the following correctly diagrams this situation? A. B. C. D. Answer: D P4.8B Predict the path of reflected light from flat, curved, or rough surfaces (e.g., flat and curved mirrors, painted walls, paper). L3 1. A ray of light strikes a mirror at 30 degrees with the normal. What is the angle between the incident ray and the reflected ray? A. B. C. D. E. 15 degrees 30 degrees 45 degrees 60 degrees 90 degrees Answer: D Physics Assessments – August 2008 Revision 87 2. A ray of light strikes a lake at 35 degrees with the normal. What is the angle between the reflected ray and the lake? A. B. C. D. 15 degrees 35 degrees 55 degrees 75 degrees Answer: C P4.8e Given an angle of incidence and indices of refraction of two materials, calculate the path of a light ray incident on the boundary (Snell’s Law). L2 1. A light ray passes through the air and strikes a smooth surface of water at an angle of 40° to the normal. The index of refraction for air is 1.00 and for water is 1.33. What is the angle of refraction? A. B. C. D. 29° 55° 16° 59° Answer: A 2. Which of the following is evidence for the particle theory of light? A. B. C. D. the way light interacts with diffraction grating the photoelectric effect the polarization of light the double-slit experiment Answer: B Physics Assessments – August 2008 Revision 88 3. At which point will destructive interference occur on the concentric waves below? A. B. C. D. 4 3 1 2 Answer: A 4. Use the diagram below to answer the question. Which diagram illustrates the direction of a particle's motion in the transverse wave above? A. B. C. D. Answer: B P4.8f Explain how Snell’s Law is used to design lenses (e.g., eye glasses, microscopes, telescopes, binoculars). L2 P4.9A Identify the principle involved when you see a transparent object (e.g., straw, a piece of glass) in a clear liquid. L1 Physics Assessments – August 2008 Revision 89 P4.9B Explain how various materials reflect, absorb, or transmit light in different ways. L2 1. The sun is shining on this house. Which is true about the wall and the window? A. B. C. D. More sun will shine on the window than on the wall. More sun will shine on the wall than on the window The window will reflect the sun better than the wall The wall will reflect the sun better than the window Answer: C 2. Which of the following reflects light the best? A. B. C. D. something clear something hot something smooth something shiny Answer: D 3. Nikita has a glass bottle and a plastic bottle. Which statement is true? A. The plastic bottle will attract more light than the glass bottle. B. The glass bottle will reflect light better than the plastic bottle. C. The plastic bottle will reflect light better than the glass bottle. D. The glass bottle and the plastic bottle will not reflect any light. Answer: B Physics Assessments – August 2008 Revision 90 4. Which of these objects will reflect light the best? A. B. C. D. a piece of metal a wooden block a sidewalk a rubber balloon Answer: A 5. In the Doppler Effect, light reaching the Earth from a distant galaxy in an expanding universe is shifted to A. B. C. D. longer wavelengths higher frequencies greater velocities greater amplitudes Answer: A 6. Which diagram correctly illustrates diffraction of light? A. B. C. D. Answer: A Physics Assessments – August 2008 Revision 91 P4.9C Explain why the image of the Sun appears reddish at sunrise and sunset. L2 1. What best explains why the image of the Sun appears reddish at Sunrise and sunset. A. The intensity of scattered light varies inversely as the fourth power of its wavelength. B. Red has the maximum wavelength; rays of light have to travel through a larger part of the atmosphere because they are closest to the horizon. C. The pollution at the horizon colors the light from the sun. D. The ratio of light reflected from a surface to light falling on a surface creates a red haze. Answer: B P4.r9d Describe evidence that supports the dual wave-particle nature of light (recommended) 1. Which of the following is evidence for the particle theory of light? A. B. C. D. the way light interacts with diffraction grating the photoelectric effect the polarization of light the double-slit experiment Answer: B Physics Assessments – August 2008 Revision 92 Unit Twelve P4.1B Explain instances of energy transfer by waves and objects in everyday activities (e.g., why the ground gets warm during the day, how you hear a distant sound, why it hurts when you are hit by a baseball). L2 P4.2D Explain why all the stored energy in gasoline does not transform to mechanical energy of a vehicle. L2 P4.11a Calculate the energy lost to surroundings when water in a home water heater is heated from room temperature to the temperature necessary to use in a dishwasher, given the efficiency of the home hot water heater. L2 1. A building contractor was given several options as to the type of building materials he could use in a house he was constructing. He was told that he could use either pine or oak for trim, and concrete, cinder block or building block for walls. The buyers instructed the contractor to build the house as thermally efficient as feasible. Building block =3-6 Cinder block=2-3 Concrete=6-9 Glass=5-6 Oak=1.02 Pine=0.78 Using the above chart of thermal conductivity, what materials would he use? A. B. C. D. E. Building block and oak Building block and pine Cinder block and oak Cinder block and pine Concrete and oak Answer: D 2. A solar heater uses energy from the sun to heat water. The heater’s panel is painted black to ______________ A. B. C. D. improve emission of infrared radiation reduce the heat loss by convection currents improve absorption of infrared radiation reduce the heater’s conducting properties Answer: C Physics Assessments – August 2008 Revision 93 P4.12A Describe peaceful technological applications of nuclear fission and radioactive decay. L2 1. Nuclear energy can be generated by fission or fusion. Fusion is not currently being used in reactors as an energy source. Why is this? A. B. C. D. The scientific principles on which fusion is based are not yet known. The technological processes for using fusion safely are not developed. The necessary raw materials are not readily available. Waste products from the fusion process are too dangerous. Answer: B P4.12B Describe possible problems caused by exposure to prolonged radioactive decay. L2 P4.12C Explain how stars, including our Sun, produce huge amounts of energy (e.g., visible, infrared, or ultraviolet light). L2 1. Which of the following statements describes nuclear fission? A. B. C. D. A large nucleus breaks down into smaller, more reactive nuclei Small nuclei combine to form larger, more stable nuclei. A large nucleus breaks down into smaller, more stable nuclei Small nuclei combine to form larger, more reactive nuclei Answer: C 2. Which of the following statements is true about nuclear fusion, but NOT nuclear fission? A. B. C. D. The reaction begins with the addition of a neutron. Small nuclei form a larger, heavier nucleus. Energy is released during the reaction. The reaction produces a more stable nucleus. Answer: B 3. What role does hydrogen gas play during the life cycle of a star? A. B. C. D. It undergoes fission which causes the star to expand. It reacts with helium, causing the star to glow brightly. It keeps the star relatively cool so it does not burn up too quickly. It undergoes fusion which generates energy in the star. Answer: D Physics Assessments – August 2008 Revision 94 4. Most stars derive their energy from _______________ . A. B. C. D. the fission of helium the radioactive decay of hydrogen ions the fusion of hydrogen the sun Answer: C P4.12d Identify the source of energy in fission and fusion nuclear reactions. L1 1. Nuclear energy can be generated by fission or fusion. Fusion is not currently being used in reactors as an energy source. Why is this? A. B. C. D. The scientific principles on which fusion is based are not yet known. The technological processes for using fusion safely are not developed. The necessary raw materials are not readily available. Waste products from the fusion process are too dangerous. Answer: B Physics Assessments – August 2008 Revision 95 Physics Assessments – August 2008 Revision 96