Page 1. Name: 1) Which terms represent scalar quantities? A) work and displacement. C) distance and velocity B) time and energy

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1 Name: Page 1 1) Which terms represent scalar quantities? work and displacement distance and velocity time and energy power and force 2) A student walks 3 blocks south, 4 blocks west, and 3 blocks north. What is the displacement of the student? 4 blocks west 10 blocks west 10 blocks east 4 blocks east 3) Oil drips at 0.4-second intervals from a car that has an oil leak. Which pattern best represents the spacing of oil drops as the car accelerates uniformly from rest? 4) Which graph represents an object moving at a constant speed for the entire time interval? 5) The average speed of a plane was 600 kilometers per hour. How long did it take the plane to travel 120 kilometers? 0.2 hour 5 hours 0.5 hour 0.7 hour 6) What is the average speed of an object that travels 6.00 meters north in 2.00 seconds and then travels 3.00 meters east in 1.00 second? m/s 9.00 m/s 4.24 m/s 3.00 m/s 7) The distance-time graph below represents the position of an object moving in a straight line. What is the speed of the object during the time interval t = 2.0 seconds to t = 4.0 seconds? 5.0 m/s 0.0 m/s 10. m/s 7.5 m/s 8) A locomotive starts from rest and accelerates at 0.12 meter per second 2 to a speed of 2.4 meters per second in 20. seconds. This motion could best be described as constant acceleration and increasing velocity constant acceleration and constant velocity increasing acceleration and increasing velocity increasing acceleration and constant velocity

2 9) Which graph best represents the motion of an object initially at rest and accelerating uniformly? Page 2 10) The diagram below shows a graph of distance as a function of time for an object in straight-line motion. According to the graph, the object most likely has a constant momentum a decreasing acceleration an increasing speed a decreasing mass 11) A race car traveling at 10. meters per second accelerates at the rate of 1.5 meters per second 2 while traveling a distance of 600. meters. The final speed of the race car is approximately 150 m/s 44 m/s 910 m/s 1900 m/s 12) A ball dropped from a bridge takes 3.0 seconds to reach the water below. How far is the bridge above water? 44 m 29 m 88 m 15 m 13) A stone is dropped from a bridge 45 meters above the surface of a river. Approximately how many seconds does the stone take to reach the water's surface? 1.0 s 22 s 3.0 s 10. s 14) In an experiment that measures how fast a student reacts, a meter stick dropped from rest falls 0.20 meter before the student catches it. The reaction time of the student is approximately 0.10 s 0.20 s 0.30 s 0.40 s 15) An object starts from rest and falls freely. What is the velocity of the object at the end of 3.00 seconds? 19.6 m/s 9.81 m/s 88.2 m/s 29.4 m/s 16) An object near the surface of planet X falls freely from rest and reaches a speed of 12.0 meters per second after it has fallen 14.4 meters. What is the acceleration due to gravity on planet X? 10.0 m/s m/s m/s m/s 2

3 Questions 17 through 19 refer to the following: Page 3 The graph below represents the displacement of an object as a function of time. 17) What is the velocity of the object at t = 1 second? 2.0 m/s 3.0 m/s 1.5 m/s 1.0 m/s 18) What is the average velocity of the object from t = 0 to t = 3 seconds? 2.0 m/s 3.0 m/s 0 m/s 1.0 m/s 19) During which time interval is the object accelerating? 0-2 s 3-4 s 4-6 s 2-3 s 20) In the graph below, the acceleration of an object is plotted against the unbalanced force on the object. What is the object's mass? 1 kg 2 kg 0.2 kg 0.5 kg 21) A 50.0-kilogram object in outer space is attracted to a nearby planet with a net force of 400. newtons. What is the magnitude of the object's acceleration? 8.00 m/s m/s m/s 2 2,000 m/s 2 22) A bullet traveling at 5.0 x 10 2 meters per second is brought to rest by an impulse of 50. newton-seconds. What is the mass of the bullet?.0 x 10-1 kg.0 x 10 1 kg.0 x 10-2 kg.5 x 10 4 kg 23) The product of an object's mass and velocity is equal to kinetic energy weight momentum force 24) A 25-kilogram mass travels east with a constant velocity of 40. meters per second. The momentum of this mass is 1.0 x 10 3 kgdm/s west 9.8 x 10 3 kgdm/s west 9.8 x 10 3 kgdm/s east 1.0 x 10 3 kgdm/s east 25) A 2-kilogram object traveling 10 meters per second north has a perfect elastic collision with a 5-kilogram object traveling 4 meters per second south. What is the total momentum after collision? 40 kgdm/s east 20 kgdm/s north 0 kgdm/s 20 kgdm/s south 26) A 2.0-kilogram ball traveling north at 4.0 meters per second collides head on with a 1.0-kilogram ball traveling south at 8.0 meters per second. What is the magnitude of the total momentum of the two balls after collision? 0 kgdm/s 8.0 kgdm/s 32 kgdm/s 16 kgdm/s

4 Page 4 27) A rocket with a mass of 1,000 kilograms is moving at a speed of 20 meters per second. The magnitude of the momentum is 20,000 kgdm/s 50 kgdm/s 400,000 kgdm/s 200 kgdm/s 28) Which is a vector quantity? energy momentum speed power 29) Two rocks weighing 5 newtons and 10 newtons, respectively, fall freely from rest near the Earth's surface. After 3 seconds of freefall, compared to the 5-newton rock, the 10-newton rock has greater acceleration speed momentum height 30) A net force of 12 newtons acting north on an object for 4.0 seconds will produce an impulse of 48 kg-m/sec south 48 kg-m/sec north 3.0 kg-m/sec south 3.0 kg-m/sec north 31) An unbalanced 6.0-newton force acts eastward on an object for 3.0 seconds. The impulse produced by the force is 18 Nds west 2.0 Nds west 2.0 Nds east 18 Nds east 32) A force of 20. newtons is exerted on a cart for 10. seconds. How long must a 50.-newton force act to produce the same impulse? 5.0 s 2.0 s 4.0 s 10. s 33) Which two graphs represent the motion of an object on which the net force is zero? 34) A baseball bat moving at high velocity strikes a feather. If air resistance is neglected, compared to the force exerted by the bat on the feather, the force exerted by the feather on the bat will be smaller the same larger 35) In the diagram below, surface A of the wooden block has twice the area of surface B. If it takes F newtons to keep the block moving at a constant speed across the table when it slides on surface A, what force is needed to keep the block moving at constant speed when it slides on surface B? 2F \F F 4F 36) A 5.0-kilogram cart moving with a velocity of 4.0 meters per second is brought to a stop in 2.0 seconds. The magnitude of the average force used to stop the cart is 4.0 newtons 2.0 newtons 20. newtons 10. newtons

5 37) A bird feeder with two birds has a total mass of 2.0 kilograms and is supported by wire as shown in the diagram below Page 5 The force in the top wire is approximately 20. N 14 N 39 N 10. N 38) A 50.-kilogram woman wearing a seat belt is traveling in a car that is moving with a velocity of +10. meters per second. In an emergency, the car is brought to a stop in 0.50 second. What force does the seat belt exert on the woman so that she remains in her seat? -5.0 x 10 2 N -1.0 x 10 3 N -2.5 x 10 1 N -5.0 x 10 1 N 39) A force of 50. newtons causes an object to accelerate at 10. meters per second squared. What is the mass of the object? 60. kg 0.20 kg 500 kg 5.0 kg 40) Work is being done when a force acts vertically on a cart that can only move horizontally is exerted while pulling a wagon up a hill is exerted by one team in a tug-of-war when there is no movement of gravitational attraction acts on a person standing on the surface of the Earth 41) The graph below shows the force exerted on a block as a function of the block's displacement in the direction of the force. How much work did the force do in displacing the block 5.0 meters? 0.80 J 0 J 20. J 4.0 J 42) A jack exerts a force of 4,500 newtons to raise a car 0.25 meter. What is the approximate work done by the jack? 1.8 x 10 4 J 4.5 x 10 3 J 5.6 x 10-5 J 1.1 x 10 3 J 43) Car A and car B are of equal mass and travel up a hill. Car A moves up the hill at a constant speed that is twice the constant speed of car B. Compared to the power developed by car B, the power developed by car A is twice as much the same four times as much half as much 44) The rate of change of work with respect to time is called energy momentum force power

6 45) Which variable expression is paired with a corresponding unit? Page 6 and watt and joule and joule and watt 46) When a 5-kilogram mass is lifted from the ground to a height of 10 meters, the gravitational potential energy of the mass is increased by approximately 2 J 500 J 0.5 J 50 J 47) If the velocity of an automobile is doubled, its kinetic energy quadruples decreases to one-fourth 48) Which cart shown below has the greatest kinetic energy? doubles decreases to one-half 49) When a spring is stretched meter from its equilibrium position, it possesses a potential energy of 10.0 joules. What is the spring constant for this spring? 500. N/m 125 N/m 250. N/m 100 N/m 50) The diagram below represents a 2.0-kilogram mass placed on a frictionless track at point A and released from rest. Assume the gravitational potential energy of the system to be zero at point E. Compared to the total mechanical energy of the system at point A, the total mechanical energy of the system at point F is the same more less