Name______________________ Chapter 11 Motion Vocabulary 1. Frame of reference 2. Distance 3. Displacement 4. Vector 5. Speed 6. Instantaneous speed 7. Average speed 8. Velocity 9. Acceleration 10. Free fall 11. Constant Acceleration 12. Linear Graph 13. Nonlinear Graph Distance and Displacement Worksheet For each question plot the path on the grid paper. 1. Stan walks 10km west to the grocery store. He shops then walks back 10 km east back to his house. What distance did he cover? What was his displacement? 2. Tyler drives 50km north. Tyler then drives back 30km south. What distance did he cover? What was his displacement? 3. Joey drives his Skidoo 7 kilometres north. He stops for lunch and then drives 5 kilometres east. What distance did he cover? What was his displacement? 4. Brittney is on the starting line to run a track race. The distance around the track is 400m. She starts the race and runs 400m around the track. She ends up in the same place where she started. What distance did she cover? What was her displacement? 5. Anthony walks to the pizza place for lunch. He walk 4 km east, he realized he passed it and then walked 1 km west. What distance did he cover? What was his displacement? 6. On his fishing trip Justin takes the boat 12 km south. The fish aren’t biting so he goes 4 km west. What distance did he cover? What was his displacement? 7. Preston goes on a camel safari in Africa. They he travels 5 km north, then 3 km east. What distance did he cover? What was his displacement? 8. Neil pogo sticks from his locker to his science class. He travels 8 m east then 8 m west back to his locker. What distance did he cover? What was his displacement? 9. Brandon buys a new Seadoo. He goes 12 km north from the beach. He jumps wakes for 6 km to the east. What distance did he cover? What was his displacement? 10. Answer on graph paper. Alan rents a private jet for the weekend. He flies 400 km south to New York, then flies 700 km west to Chicago, then 1200 km south to Miami. What distance did he cover? What was his displacement? (use 1cm = 100km) *Use a ruler to find the straight line displacement 11. Answer on graph paper. Alex goes cruising on his dirt bike. He rides 700 m north, 300 m east, 400 m north, 600 m west, 1200 m south 300 m east and finally 100 m north. What 12. distance did he cover? What was his displacement? (use 1cm = 100m) *Use a ruler to find the straight line displacement DISTANCE, TIME, SPEED PRACTICE PROBLEMS YOU MUST SHOW YOUR WORK. You can use a calculator but you must show all of the steps involved in doing the problem. SPEED 1. If a car travels 400m in 20 seconds how fast is it going? 2. If you move 50 meters in 10 seconds, what is your speed? 3. You arrive in my class 45 seconds after leaving math which is 90 meters away. How fast did you travel? 4. A plane travels 395,000 meters in 9000 seconds. What was its speed? 5. It takes Serina 0.25 hours to drive to school. Her route is 16 km long. What is Serina’s average speed on her drive to school? TIME 6. How much time will it take for a bug to travel 5 meters across the floor if it is traveling at 1 m/s? 7. You need to get to class, 200 meters away, and you can only walk in the hallways at about 1.5 m/s. (if you run any faster, you’ll be caught for running). How much time will it take to get to your class? 8. In a competition, an athlete threw a flying disk 139 meters through the air. While in flight, the disk traveled at an average speed of 13.0 m/s. How long did the disk remain in the air? DISTANCE 9. How far can you get away from your little brother with the squirt gun filled with paint if you can travel at 3 m/s and you have 15s before he sees you? 10. How far can your little brother get if he can travel at 2.5 m/s and in 5 seconds you will discover that his squirt gun has run out of paint? 11. If you shout into the Grand Canyon, your voice travels at the speed of sound (340 m/s) to the bottom of the canyon and back, and you hear an echo. How deep is the Grand Canyon at a spot where you can hear your echo 5.2 seconds after you shout? CHALLENGE PROBLEM Bill and Amy want to ride their bikes from their neighborhood to school which is 14.4 kilometers away. It takes Amy 40 minutes to arrive at school. Bill arrives 20 minutes after Amy. How much faster (in meters/second) is Amy’s average speed for the entire trip? Be sure to show all necessary metric conversions!! Acceleration Notes Acceleration is the rate of change in the speed of an object. To determine the rate of acceleration, you use the formula below. The units for acceleration are meters per second per second or m/s2. Acceleration formula: A positive value for acceleration shows speeding up, and negative value for acceleration shows slowing down. Slowing down is also called deceleration. The acceleration formula can be rearranged to solve for other variables such as final speed (v2) and time (t). Final Speed (V2): Time (t): EXAMPLES 1. A skater increases her velocity from 2.0 m/s to 10.0 m/s in 3.0 seconds. What is the skater’s acceleration? Looking for Solution Given Formula 2. A car accelerates at a rate of 3.0 m/s2. If its original speed is 8.0 m/s, how many seconds will it take the car to reach a final speed of 25.0 m/s? Looking for Given Solution Formula Name: _________________________ Acceleration Practice Problems Date: ______________ 1. While traveling along a highway a driver slows from 24 m/s to 15 m/s in 12 seconds. What is the automobile’s acceleration? (Remember that a negative value indicates a slowing down or deceleration.) 2. A parachute on a racing dragster opens and changes the speed of the car from 85 m/s to 45 m/s in a period of 4.5 seconds. What is the acceleration of the dragster? 3. The table below includes data for a ball rolling down a hill. Fill in the missing data values in the table and determine the acceleration of the rolling ball. Time (seconds) Speed (km/h) 0 (start) 0 (start) 2 3 6 9 8 10 15 Acceleration = ___________________________ 4. A car traveling at a speed of 30.0 m/s encounters an emergency and comes to a complete stop. How much time will it take for the car to stop if it decelerates at -4.0 m/s2? 5. If a car can go from 0 to 60 mi/hr in 8.0 seconds, what would be its final speed after 5.0 seconds if its starting speed were 50 mi/hr? 6. A cart rolling down an incline for 5.0 seconds has an acceleration of 4.0 m/s2. If the cart has a beginning speed of 2.0 m/s, what is its final speed? 7. A helicopter’s speed increases from 25 m/s to 60 m/s in 5 seconds. What is the acceleration of this helicopter? 8. As she climbs a hill, a cyclist slows down from 25 mi/hr to 6 mi/hr in 10 seconds. What is her deceleration? 9. A motorcycle traveling at 25 m/s accelerates at a rate of 7.0 m/s2 for 6.0 seconds. What is the final speed of the motorcycle? 10. A car starting from rest accelerates at a rate of 8.0 m/s/s. What is its final speed at the end of 4.0 seconds? 11. After traveling for 6.0 seconds, a runner reaches a speed of 10 m/s. What is the runner’s acceleration? 12. A cyclist accelerates at a rate of 7.0 m/s2. How long will it take the cyclist to reach a speed of 18 m/s? 13. A skateboarder traveling at 7.0 meters per second rolls to a stop at the top of a ramp in 3.0 seconds. What is the skateboarder’s acceleration? ACCELERATION PRACTICE PROBLEMS YOU MUST SHOW YOUR WORK. You can use a calculator but you must show all of the steps involved in doing the problem. SHORT ANSWER 1. Does the speedometer of a car read average speed or instantaneous speed? How do you know? 2. If the speedometer of your car reads a constant speed of 40km/hr, can you say 100% for sure that the car has a constant velocity? Explain your answer. 3. What two controls on a car cause a change in speed? 4. What control causes a change in velocity? 5. What is the acceleration of a car that travels in a straight line at a constant speed? 6. Describe a situation in which you can accelerate even though your speed doesn’t change. CALCULATIONS 7. A roller coaster car rapidly picks up speed as it rolls down a slope. As it starts down the slope, its speed is 4 m/s. But 3 seconds later, at the bottom of the slope, its speed is 22 m/s. What is its average acceleration? 8. A cyclist accelerates from 0 m/s to 8 m/s in 3 seconds. What is his acceleration ? Is this acceleration higher than that of a car which accelerates from 0 to 30 m/s in 8 seconds? 9. A car advertisement states that a certain car can accelerate from rest to 70 km/h in 7 seconds. Find the car’s average acceleration. 10. A lizard accelerates from 2 m/s to 10 m/s in 4 seconds. What is the lizard’s average acceleration? 11. A runner covers the last straight stretch of a race in 4 s. During that time, he speeds up from 5 m/s to 9 m/s. What is the runner’s acceleration in this part of the race? 12. You are traveling in a car that is moving at a velocity of 20 m/s. Suddenly, a car 10 meters in front of you slams on it’s brakes. At that moment, you also slam on your brakes and slow to 5 m/s. Calculate the acceleration if it took 2 seconds to slow your car down. 13. A ball is dropped from the top of a building. After 2 seconds, it’s velocity is measured to be 19.6 m/s. Calculate the acceleration for the dropped ball.
