Physics Questions

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Physics

Name:

Section 1

Matching

___ 1. Speed

___ 2. Momentum

___ 3. Velocity

___ 4. Centripetal

___ 5. Uniform circular motion a. an increase in velocity over time b. 9.8 meters per second per second c. away from the center d. a decrease in velocity over time e. 60 kilometers per hour west

___ 6. Acceleration

___ 7. g

___ 8. Centrifugal

___ 9. Deceleration f. an apple sits motionless on a desk g. dependent on mass and velocity h. toward the center i. 25 miles per hour j. motion of a clothes dryer ___ 10. Law of inertia

Multiple-Choice Questions

___ 11. A change in position relative to a body assumed to be at rest is called a. motion b. momentum c. inertia d. acceleration

___ 12. The average velocity can be determined from the formula a. time/distance c. distance/time b. time/acceleration d. distance x time

___ 13. The distance covered by a car traveling at an average velocity of 50 mph for 5

hours is a. 10 miles b. 250 miles

___ 14. The rate of change of velocity is called c. 55 miles d. 45 miles a. acceleration b. motion c. momentum d. inertia

___ 15. Consider a ball rolling down an inclined plane: The greatest acceleration occurs

when the plane is at an angle of a. 60° b. 0° c. 90° d. 30°

___ 16. The acceleration due to gravity has been found to be a. 980 feet/second

2

c. 32 centimeters/second

2 b. 32 feet/second

2

d. 32 feet/second

___ 17. The scientist who hypothesized that the acceleration produced by gravity is the

same for all objects is a. Galileo b. Newton c. Copernicus d. Archimedes

___ 18. In a "coin and feather" jar, the feather falls at a slower rate than the coin because of a. inertia b. buoyant force c. momentum d. air resistance

___ 19. The symbol used to represent the gravitational constant for falling bodies is a. a b. v c. g d. t

___ 20. A body at rest tends to remain at rest and a body in motion tends to remain

in motion unless acted upon by an unbalanced force is stated in the law of a. motion b. inertia c. momentum d. action and reaction

___ 21. A moving bus comes to a sudden stop and the passengers lurch forward. This is

an example of a. velocity b. momentum c. acceleration d. deceleration

___ 22. As the force acting on an object decreases, the acceleration of the object a. increases c. remains the same b. decreases d. increases, then decreases

___ 23. As the mass of an object increases, the acceleration of that object a. increases c. remains the same b. decreases d. increases, then decreases

___ 24. The momentum of a body is the product of the mass of the body and its a. acceleration b. distance c. speed d. height

___ 25. The motion of a jet aircraft is primarily based on the law of a. action and reaction c. momentum b. inertia d. conservation of energy

___ 26. An inward force created by uniform circular motion is called a. buoyant force c. centripetal force b. centrifugal reaction d. gravity

True (T) or False (F)

___ 27. The distance traveled by an object in a unit of time is called speed.

___ 28. The slowing down of a car in a given time is called velocity.

___ 29. Newton has 4 laws of motions.

___ 30. One of the first scientists to study the rate of gravitational acceleration was Newton.

___ 31. In the metric system, the gravitational acceleration has been found to be 9.8 meters per

second

2

___ 32. The gravitational constant for acceleration varies for every object studied.

___ 33. The force acquired by a moving body because of its motion is called inertia

___ 34. Newton's third law is also known as the law of acceleration.

___ 35. A car can have a velocity of 50 miles per hour northeast.

___ 36. In a vacuum, all objects fall at the same rate.

Testing Your Knowledge: Show all work to receive credit.

37. A stone that is dropped from the top of a building strikes the ground in 10 seconds.

A. Compute the height of the building in feet.

B. What is the velocity of the stone at the end of the 7th second?

38. Find the acceleration of an object, whose mass is 50 kilograms, that is being acted upon by an unbalanced force of 200 newtons. (Newton = 1 kg x m/sec.

2 )

Find the scrambled term that matches each clue. Then unscramble it, and write it next to the clue. talicecerona trainie yolevict tommemun lateptricne crofe desep vragyti

____________ 39. the rate of change in velocity

____________ 40. describes the speed and direction of an object

____________ 41. the force of an object pulling towards the center of a circular path

____________ 42. the rate of change in position

____________ 43. property of a body that resists any change in velocity

____________ 44. mass of an object multiplied by its velocity

____________ 45. a push or pull exerted on one body by another

____________ 46. a force that acts on all objects on Earth

Identify which of Newton’s law apply to each: First (1), Second (2) or Third (3)?

_____ 47. A frog leaping upward off his lily pad is pulled downward by gravity and lands on

another lily pad instead of continuing on in a straight line.

_____ 48. As the fuel in a rocket ignites, the force of the gas expansion and explosion pushes

out the back of the rocket and pushes the rocket forward.

_____ 49. When you are standing up on a bus, and the bus suddenly stops, your body continues

forward.

_____ 50. A pitched baseball goes faster than one that is gently thrown.

_____ 51. A swimmer pushes water back with her arms, but her body moves forward.

_____ 52. As an ice skater pushes harder with her legs, she begins to move faster.

_____ 53. When you paddle a canoe, the canoe goes forward.

Name:

Physics

Section 2

Multiple-Choice

___1. Work is defined as the product of a. force and weight c. force and energy b. energy and height d. force and distance

___2. In the English system of measurement, the unit of work is the a. foot-pound b. pound-foot c. watt d. newton-meter

___3. In the metric system of measurement, the unit of work is the b. pound-foot c. watt d. newton-meter a. foot-pound

___4. In any machine a. some of the effort applied is lost to friction b. all the effort applied is lost to friction c. none of the effort applied is lost to friction

___5. When doing work, a reduction in effort is generally accompanied by a. no change in the distance b. a decrease in the distance covered by the effort c. a decrease in height d. an increase in the distance covered by the effort

___6. A machine that makes it possible to move a resistance faster is a a. wedge b. lever c. screw d. wheel-and-axle

___7. In an ideal machine, the work input a. is greater than the work output b. is less than the work output c. is equal to the work output d. never changes

___8. The product of the resistance and the distance through which the resistance is

moved is called the a. law of machines b. work input c. work output d. effort

___9. When 30 pounds of effort are applied to a machine with a mechanical advantage

of 3, the machine produces an effort of a. 10 pounds b. 30 pounds c. 90 pounds d. 15 pounds

___10. The ideal mechanical advantage refers to a machine that a. has no friction c. produces large amounts of friction b. needs no effort d. is easy to build

___11. Mechanical advantage is found by dividing the resistance by the a. effort b. resistance distance c. friction d. effort distance

___12. The amount by which a machine multiplies an effort force is called the a. mechanical advantage c. effort multiplier b. force ratio d. work input

___13. The rate of doing work is called a. power b. effort c. energy d. mechanical advantage

___14. One horsepower is equal to a. 700 foot-pounds c. 550 foot-pounds

Matching b. 500 watts d. 1 kilowatt

___15. Ideal machine

___16. Watt

___17. MA

___18. Bernoulli’s Principle

___19. Lift a. metric unit of power b. resistance divided by the effort c. an upward force d. frictionless machine e. pressure exerted by a fluid in motion is less then when

at rest

True(T) or False(F)

___20. The force exerted when a person moves an object is called the resistance force.

___21. The actual work put into a machine is called work input.

___22. The equal nature of work input and work output of a machine is expressed in the law of

power.

___23. In the metric system, power is expressed in a unit called a foot-pound.

___24. One thousand pounds are equal to a milliwatt.

___25. If a boy pushes a car and it does not move, he is still doing work.

___26. Work is equal to the applied force multiplied by the distance an object is moved.

Testing Your Knowledge: Show all work to receive credit.

27. Compute the work performed by a man who exerts 600 newtons of force on a sled and moves it

6 meters.

28. 1000 foot-pounds of work are performed by a force of 50 pounds. Over what distance did the object move?

29. Find the power developed when a force of 1100 newtons moves an object a distance of 23 meters in 2 seconds.

Name:

Physics

Section 3

Matching

___1. First-class lever a. axe

___2. Second-class lever b. spiral staircase

___3. Wedge c. doorknob

___4. Third-class lever

___5. Inclined plane

___6. Screw

___7. Wheel-and-axle d. pair of pliers e. sugar tongs f. ramp g. wheelbarrow

Tell what simple machine is represented by each picture (Hint: look at the circled area)

8. A = ________________

9. B = ________________

10. C = ________________

11. D = ________________

12. E = ________________

13. F = ________________

14. G = ________________

15. H = ________________

16. I = ________________

17. J = ________________

18. K = ________________

19. L = ________________

20. M = ________________

21. N = ________________

22. O = ________________

True(T) or False(F)

___23. When a pulley is attached to the resistance and moves with it, it is known as a movable

pulley.

___24. A modified double inclined plane describes a simple machine known as a screw.

___25. An inclined plane that is wrapped around a cylinder is called a wedge.

___26. The distance between two successive ridges of a screw is called the pitch.

___27. The mechanical advantage of the wedge depends on its slope (length) and thickness.

Testing Your Knowledge: Show all work to receive credit.

28. Calculate the effort needed to raise a resistance of 150 pounds using a windlass. The radius of the wheel is 15 inches while the radius of the axle is 3 inches.

29. a. A 200-newton object is moved by a lever whose fulcrum is 1 meter from the object. The effort needed to move the object is exerted 2 meters on the other side of the fulcrum. Find the mechanical advantage of the lever. b. What effort force was needed to move the object?

30. a. What is the MA of an inclined plane 20 feet long with a height of 4 feet? b. Find the effort necessary to move a 100-pound object up the inclined plane.

Multiple-Choice

___ 31. A device that consists of only one part that changes the size or direction of a force is a ___. a. force driver b. simple machine c. force mechanism d. reaction mechanism

___ 32. Two inclined planes put together form a simple machine called a a. lever b. winch c. screw d. wedge

___ 33. In an inclined plane, the distance through which the resistance moves a. is the same as the length of the plane b. is greater than the length of the plane c. is the height of the plane d. is less than the height of the plane

___ 34. A winding mountain road is an example of what kind of simple machine? a. lever b. wheel and axle c. pulley d. inclined plane

___ 35. An example of a first-class lever is a a. see-saw b. wheelbarrow c. nutcracker d. sugar tongs

___ 36. When the resistance in a lever lies somewhere between the effort and the fulcrum, it is a. a first-class lever c. a third-class lever b. a second-class lever d. none of these

___ 37. An example of a third-class lever is a a. wheel barrow b. sugar tongs c. pliers d. nutcracker

___ 38. Of the following, the simple machine that provides a mechanical advantage of 1is a a. second-class lever c. single fixed pulley b. single movable pulley d. screw

___ 39. An arrangement of pulleys designed to reduce the effort force is called a ____. a. fixed pulley b. trolley c. movable pulley d. block and tackle

___ 40. A simple machine used in a steering wheel and a bicycle is a a. lever b. wedge c. pulley d. wheel-and-axle

___ 41. The mechanical advantage of a wheel-and-axle equals a.

the radius of the larger wheel divided by the radius of the axle b.

the radius of the axle divided by the radius of the wheel c.

the effort divided by the resistance d.

the effort distance multiplied by the resistance distance

Use the words in the box to fill in the blanks.

What is a Simple Machine? into increase machine one applied force compound simple six more

A job can be made easier by changing the size or direction of the force you must exert when using a

(42)_____________. A simple machine is a machine consisting of only (43)______________ part.

There are (44)______________ types of simple machines. A bicycle is a (45)_____________ machine. A bicycle is made of more than one (46)_____________ machine. Some machines make a job easier because they increase the amount of (47)_______________ you can exert. The resistance force is the force exerted by the machine. The effort force is the force (48)_____________ to the machine. The work put out by a machine is never (49)_____________ than the work put

(50)_____________ it. A machine cannot (51)_____________ the amount of work done.

The Lever longer applied force position acts fulcrum lever effort

A bar that is free to pivot about a fixed point is called a (52)_____________. The point at which a lever pivots is called the (53)_______________. An effort force is applied to a lever on the

(54)____________arm. The resistance arm exerts the resistance (55)_____________. The length of the effort arm is the distance from the fulcrum to the place where the effort force is

(56)_____________. The length of the resistance arm is the distance from the fulcrum to the place where the resistance force (57)_____________ _ _. If the effort force is smaller than the resistance force, the effort arm must be (58)___________ ____ than the resistance arm. The three classes of levers differ in the (59)________________ of the fulcrum, effort force, and resistance force.

Pulleys direction movable supporting raise simple block weight lever

A pulley is a (60) _________ ___ machine that acts like a (61)________________. A fixed pulley can be used to change the (62)________________ of the effort force. The pulley will act like a lever with an MA of one. By using the pulley, you can (63)_____________ an object while standing on the ground. To reduce the effort force needed for work, one can use a

(64) _____________ pulley. For a movable pulley, the effort arm is equal to both ropes that support the resistance arm. With a movable pulley, the rope must be pulled up twice as far as the

(65)_____________ rises. A person can lift heavy machinery with an arrangement of several pulleys called a (66)_______________ and tackle. The mechanical advantage of an ideal block and tackle is equal to the number of ropes (67)_______________ the resistance weight.

The Wheel and Axle teeth resistance wheel larger axle effort gear

A simple machine that consists of a large wheel fixed to a smaller wheel or shaft is called a

(68)________________ and axle. The radius of the wheel is (69)_______________ than the radius of the axle. A crank used to lift a bucket of water from a well is a wheel and (70)______________.

The force applied by your hand on the crank handle is the (71)______________ force. The force exerted on a rope wrapped around an axle is the (72) _______________ force. To prevent slippage, the wheel or axle can have (73)_____________ cut into it. It is then called a (74)______________.

To transfer the force from one gear to the next, the two gears can touch each other, or a chain can be used.

Inclined Plane, Screw, and Wedge raise friction inclined plane sloping wedge screw length

A plank is a simple machine called an (75)__________ ____________. An inclined plane is a slanted surface used to (76)_____________ objects. The mechanical advantage of an inclined plane is the ratio of the (77)_______________ of the plane to the height. While the MA of an inclined plane can be used to predict the force needed to move objects, under actual conditions it takes more force to push an object up a ramp because the force of (78)______________ must be overcome. An inclined plane with either one or two sloping sides is called a (79)_____________. A knife blade is a wedge with two (80)_______________sides. An inclined plane wound around a cylinder is called a (81)_________________.

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