# Quiz 3: Forces and Motion in One Dimension

Physics & Astronomy

Q 1Q 1

Starting from rest, a car accelerates down a straight road with constant acceleration a

_{1}for a time t_{1}, then the acceleration is changed to a different constant value a_{2 }for an additional time t_{2}. The total elapsed time is t_{1}+ t_{2}. Can the equations for motion with constant acceleration be used to find the total distance traveled? A) No, because this is not a case of constant acceleration. B) Yes, use (a_{1}+ a_{2})/2 as the average acceleration and the total time in the calculation. C) Yes, use a_{1}+ a_{2}as the acceleration and the average time (t_{1}+ t_{2})/2 in the calculation. D) Yes, break the problem up into 2 problems, one with the conditions for the first time interval and the other with the conditions for the second time interval, noting that for the second time interval the initial velocity is that from the end of the first time interval. When done, add the distances from each of the time intervals.Free

Multiple Choice

D

Q 2Q 2

Starting from rest, a car accelerates down a straight road with constant acceleration a for a time t, then the direction of the acceleration is reversed, i.e., it is a, and the car comes to a stop in an additional time t, the time for the whole trip being 2t. At what time, or times, is the average velocity of the car for the trip equal to its instantaneous velocity during the trip?
A) There is no such time.
B) It is at the halfway point at t.
C) This occurs at 2 times, at 0.5 t and 1.5 t.
D) This occurs at 2 times, at 0.707 t and 1.293 t.

Free

Multiple Choice

C

Q 3Q 3

A ball rolls down an incline, starting from rest. If the total time it takes to reach the end of the incline is T, how much time has elapsed when it is halfway down the incline?
A) 0.5T
B) < 0.5T
C) > 0.5T
D) More information is needed.

Free

Multiple Choice

C

Q 4Q 4

A cheetah can run at approximately 100 km/hr and a gazelle at 80.0 km/hr. If both animals are running at full speed, with the gazelle 60.0 m ahead, how long before the cheetah catches its prey?
A) 6.30 s
B) 21.6 s
C) 5.40 s
D) 10.8 s

Free

Multiple Choice

Q 5Q 5

A cheetah can maintain its maximum speed of 100 km/hr for 35.0 seconds. What minimum distance must a gazelle running 80.0 km/hr be ahead of the cheetah to escape?
A) 194 m
B) 167 m
C) 70.0 m
D) 125 m

Free

Multiple Choice

Q 6Q 6

A cart is given an initial velocity of 5.0 m/s and experiences a constant acceleration of 4.0 m/s

^{2}. What is the magnitude of the cart's displacement during the first 6.0 s of its motion? A) 10 m B) 55 m C) 66 m D) 102 mFree

Multiple Choice

Q 7Q 7

A vehicle designed to operate on a drag strip accelerates from zero to 30 m/s while undergoing a straight line path displacement of 60 m. What is the vehicle's acceleration if its value may be assumed to be constant?
A) 2.0 m/s

^{2}B) 7.5 m/s^{2}C) 10 m/s^{2}D) 15 m/s^{2}Free

Multiple Choice

Q 8Q 8

When a drag strip vehicle reaches a velocity of 60 m/s, it begins a negative acceleration by releasing a drag chute and applying its brakes. While reducing its velocity back to zero, its acceleration along a straight line path is a constant 6.0 m/s

^{2}. What displacement does it undergo during this deceleration period? A) 120 m B) 300 m C) 320 m D) 240 mFree

Multiple Choice

Q 9Q 9

A European sports car dealer claims that his product will accelerate at a constant rate from rest to a speed of 100 km/hr in 9.00 s. What distance will the sports car travel during the 9.00 s acceleration period? (Hint: First convert speed to m/s.)
A) 55.5 m
B) 125 m
C) 111 m
D) 250 m

Free

Multiple Choice

Q 10Q 10

Norma releases a bowling ball from rest; it rolls down a ramp with constant acceleration. After half a second it has traveled 0.40 m. How far has it traveled after two seconds?
A) 3.2 m
B) 6.4 m
C) 9.0 m
D) 16 m

Free

Multiple Choice

Q 11Q 11

An automobile driver puts on the brakes and decelerates from 30.0 m/s to zero in 12.0 s. What distance does the car travel?
A) 150 m
B) 180 m
C) 360 m
D) 750 m

Free

Multiple Choice

Q 12Q 12

A drag racer starts from rest and accelerates at 8.0 m/s

^{2}for the entire distance of 400 m (1/4 mile). What is the speed of the race car at the end of the run? A) 32 m/s B) 40 m/s C) 64 m/s D) 80 m/sFree

Multiple Choice

Q 13Q 13

A Cessna aircraft has a liftoff speed of 120 km/hr. What minimum constant acceleration does this require if the aircraft is to be airborne after a takeoff run of 200 m?
A) 2.31 m/s

^{2}B) 2.78 m/s^{2}C) 4.63 m/s^{2}D) 5.55 m/s^{2}Free

Multiple Choice

Q 14Q 14

If the displacement of an object is given in SI units by x = 5t + t

^{ 2}, at t = 2 s its velocity and acceleration are, respectively: (Hint: Use dimensional analysis along with the equations for motion with constant acceleration.) A) positive, positive. B) positive, negative. C) negative, negative. D) negative, positive.Free

Multiple Choice

Q 15Q 15

A rock is rolled in the sand. It starts at 5.0 m/s, moves in a straight line for a distance of 6.0 m, and then stops. What is the magnitude of the average acceleration?
A) 2.1 m/s

^{2}B) 4.2 m/s^{2}C) 5.4 m/s^{2}D) 6.2 m/s^{2}Free

Multiple Choice

Q 16Q 16

Rita accelerates a 0.40-kg ball from rest to 12 m/s during the 0.15 s in which her foot is in contact with the ball. What average force does she apply to the ball during the kick?
A) 48 N
B) 32 N
C) 24 N
D) 64 N

Free

Multiple Choice

Q 17Q 17

A barefoot field-goal kicker imparts a speed of 30 m/s to a football at rest. If the football has a mass of 0.50 kg and time of contact with the football is 0.020 s, what is the force exerted on the foot?
A) 190 N
B) 380 N
C) 600 N
D) 750 N

Free

Multiple Choice

Q 18Q 18

An automobile of mass 2000 kg moving at 20 m/s is braked suddenly with a constant braking force of 10,000 N. How far does the car travel before stopping?
A) 40 m
B) 80 m
C) 120 m
D) 160 m

Free

Multiple Choice

Q 19Q 19

A shot-putter moves his arm and the 7.0-kg shot through a distance of 1.0 m, giving the shot a velocity of 15 m/s from rest. Find the average force exerted on the shot during this time.
A) 197 N
B) 394 N
C) 600 N
D) 790 N

Free

Multiple Choice

Q 20Q 20

A baseball batter hits an incoming 40 m/s fastball. The ball leaves the bat at 60 m/s after a ball-on-bat contact time of 0.030 s. What is the force exerted on the 0.15 kg baseball?
A) 450 N
B) 250 N
C) 90 N
D) 500 N

Free

Multiple Choice

Q 21Q 21

A karate master strikes a board with an initial velocity of 10.0 m/s, decreasing to 2.0 m/s as his hand passes through the board. If the time of contact with the board is 0.0020 s, and the mass of the coordinated hand and arm is 1.0 kg, what is the force exerted on the board?
A) 1000 N
B) 6000 N
C) 4000 N
D) 4500 N

Free

Multiple Choice

Q 22Q 22

Suppose the position of a particle is given by in SI units. What are the initial velocity and the acceleration of the particle?
A)
B)
C)
D)

Free

Multiple Choice

Q 23Q 23

A speeding car traveling at a constant velocity of v passes a police car initially at rest beside the roadway. If the police car with constant acceleration of a immediately pursues the speeding car, how long is it before the police car starts gaining on the speeding car?
A)
B)
C)
D)

Free

Multiple Choice

Q 24Q 24

A speeding car traveling at a constant velocity of 24 m/s passes a police care initially at rest beside the roadway. If the police car with constant acceleration of immediately pursues the speeding car, how far down the road does it draw even with the speeding car?
A) 190 m
B) 290 m
C) 380 m
D) 770 m

Free

Multiple Choice

Q 25Q 25

The acceleration due to gravity on the Moon's surface is one-sixth that on Earth. An astronaut's life support backpack weighs 240 lb on Earth. What does it weigh on the Moon?
A) 40 lb
B) 120 lb
C) 80 lb
D) 240 lb

Free

Multiple Choice

Q 26Q 26

A 70.0-kg man jumps 1.00 m down onto a concrete walkway. His downward motion stops in 0.04 seconds. If he forgets to bend his knees, what force is transmitted to his leg bones?
A) 700 N
B) 4000 N
C) 8000 N
D) 16,000 N

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Multiple Choice

Q 27Q 27

An elevator weighing 20,000 N is supported by a steel cable. What is the tension in the cable when the elevator is being accelerated upward at a rate of 2.00 m/s

^{2}? (g = 9.80 m/s^{2}) A) 13,900 N B) 23,100 N C) 24,100 N D) 26,100 NFree

Multiple Choice

Q 28Q 28

As a basketball player starts to jump for a rebound, he begins to move upward faster and faster until he leaves the floor. During this time that he is in contact with the floor, the force of the floor on his shoes is:
A) bigger than his weight.
B) equal in magnitude and opposite in direction to his weight.
C) less than his weight.
D) zero.

Free

Multiple Choice

Q 29Q 29

As a 3.0-kg bucket is being lowered into a 10-m deep well, starting from the top, the tension in the rope is 19.6 N. The acceleration of the bucket will be:
A) 6.5 m/s

^{2}downward. B) 9.8 m/s^{2}upward. C) zero. D) 3.3 m/s^{2}downward.Free

Multiple Choice

Q 30Q 30

Three identical 6.0-kg cubes are placed on a horizontal frictionless surface in contact with one another. The cubes are lined up from left to right and a force is applied to the left side of the left cube causing all three cubes to accelerate to the right at 3.0 m/s

^{2}. What is the magnitude of the force exerted on the middle cube by the left cube in this case? A) 18 N B) 27 N C) 54 N D) none of the aboveFree

Multiple Choice

Q 31Q 31

Three identical 6.0-kg cubes are placed on a horizontal frictionless surface in contact with one another. The cubes are lined up from left to right and a force is applied to the left side of the left cube causing all three cubes to accelerate to the right at 3.0 m/s

^{2}. What is the magnitude of the force exerted on the right cube by the middle cube in this case? A) 12 N B) 18 N C) 24 N D) none of the aboveFree

Multiple Choice

Q 32Q 32

A block of mass 5.00 kg rests on a horizontal surface where the coefficient of kinetic friction between the two is 0.200. A string attached to the block is pulled horizontally, resulting in a 3.00 m/s

^{2}acceleration by the block. Find the tension in the string. (g = 9.80 m/s^{2}) A) 0.200 N B) 9.80 N C) 19.8 N D) 24.8 NFree

Multiple Choice

Q 33Q 33

A horizontal force of 1000 N is needed to overcome the force of static friction between a level floor and a 250-kg crate. If g = 9.8 m/s

^{2}, what is the coefficient of static friction? A) 4.0 B) 0.51 C) 0.41 D) 0.31Free

Multiple Choice

Q 34Q 34

A horizontal force of 750 N is needed to overcome the force of static friction between a level floor and a 250-kg crate. What is the acceleration of the crate if the 750-N force is maintained after the crate begins to move and the coefficient of kinetic friction is 0.16?
A) 1.8 m/s

^{2}B) 1.4 m/s^{2}C) 3.0 m/s^{2}D) 2.1 m/s^{2}Free

Multiple Choice

Q 35Q 35

Doug hits a hockey puck, giving it an initial velocity of 7.0 m/s. If the coefficient of kinetic friction between ice and puck is 0.050, how far will the puck slide before stopping?
A) 19 m
B) 25 m
C) 37 m
D) 50 m

Free

Multiple Choice

Q 36Q 36

It is late and Carlos is sliding down a rope from his third floor window to meet his friend Juan. As he slides down the rope faster and faster, he becomes frightened and grabs harder on the rope, increasing the tension in the rope. As soon as the upward tension in the rope becomes equal to his weight:
A) Carlos will stop.
B) Carlos will slow down.
C) Carlos will continue down at a constant velocity.
D) the rope must break.

Free

Multiple Choice

Q 37Q 37

Three identical 3.0-kg cubes are placed on a horizontal surface in contact with one another. The cubes are lined up from left to right and an 18-N force is applied to the left side of the left cube causing all three cubes to accelerate to the right. If the cubes are each subject to a frictional force of 3.0 N, what is the magnitude of the force exerted on the middle cube by the left cube in this case?
A) 18 N
B) 6 N
C) 12 N
D) none of the above

Free

Multiple Choice

Q 38Q 38

Three identical 3.0-kg cubes are placed on a horizontal surface in contact with one another. The cubes are lined up from left to right and an 18-N force is applied to the left side of the left cube causing all three cubes to accelerate to the right. If the cubes are each subject to a frictional force of 3.0 N, what is the magnitude of the force exerted on the right cube by the middle cube in this case?
A) 18 N
B) 6 N
C) 12 N
D) none of the above

Free

Multiple Choice

Q 39Q 39

As a car moves forward on a level road at constant velocity, the total force acting on the tires is:
A) greater than the normal force times the coefficient of static friction.
B) equal to the normal force times the coefficient of static friction.
C) the normal force times the coefficient of kinetic friction.
D) zero.

Free

Multiple Choice

Q 40Q 40

As a car skids with its wheels locked trying to stop on a road covered with ice and snow, the force of friction between the icy road and the tires will usually be:
A) greater than the normal force of the road times the coefficient of static friction.
B) equal to the normal force of the road times the coefficient of static friction.
C) less than the normal force of the road times the coefficient of static friction.
D) greater than the normal force of the road times the coefficient of kinetic friction.

Free

Multiple Choice

Q 41Q 41

There are six books in a stack, each with a weight of 3.0 N. The coefficient of friction between all the books is 0.20 as is the coefficient between the table and the bottom book. What horizontal push must I just exceed on the next to bottom book to start sliding the top five books off the bottom one?
A) 1.0 N
B) 5.0 N
C) 3.0 N
D) 7.0 N

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Multiple Choice

Q 42Q 42

Hector drives a pickup truck horizontally at 15.0 m/s. He is transporting a crate of delicate lead crystal. If the coefficient of static friction between the crate and the truck bed is 0.300, what is the minimum stopping distance for the truck so the crate will not slide?
A) 28.7 m
B) 51.0 m
C) 38.3 m
D) 44.4 m

Free

Multiple Choice

Q 43Q 43

The coefficient of friction between a racecar's wheels and the track is 1.0. The car starts from rest and accelerates at a constant rate for 300 m. Find the maximum speed at the end of the race.
A) 44 m/s
B) 77 m/s
C) 89 m/s
D) 99 m/s

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Multiple Choice

Q 44Q 44

A hockey puck moving at 8.0 m/s coasts to a halt in 75 m on a smooth ice surface. What is the coefficient of friction between the ice and the puck?
A) µ = 0.025
B) µ = 0.033
C) µ = 0.12
D) µ = 0.044

Free

Multiple Choice

Q 45Q 45

The maximum possible value for the coefficient of static friction is:
A) 0.50
B) 1.00
C) a value up to but not quite 1.00
D) greater than 1.00

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Multiple Choice

Q 46Q 46

A rock is thrown straight down with an initial velocity of 17.5 m/s from a cliff. What is the rock's displacement after 2.0 s? (Acceleration due to gravity is 9.80 m/s

^{2}.) A) 28 m B) 49 m C) 55 m D) 64 mFree

Multiple Choice

Q 47Q 47

A rock is thrown straight up with an initial velocity of 30.0 m/s.What maximum height will the rock reach before starting to fall downward? (Acceleration due to gravity is 9.80 m/s

^{2}.) A) 9.80 m B) 19.6 m C) 20.4 m D) 45.9 mFree

Multiple Choice

Q 48Q 48

A rock is thrown straight up with an initial velocity of 24.5 m/s. What time interval elapses between the rock's being thrown and its return to the original launch point? (Acceleration due to gravity is 9.80 m/s

^{2}.) A) 4.00 s B) 5.00 s C) 8.00 s D) 10.0 sFree

Multiple Choice

Q 49Q 49

Two objects of different mass are released simultaneously from the top of a 20-m tower and fall to the ground. If air resistance is negligible, which statement best applies?
A) The greater mass hits the ground first.
B) Both objects hit the ground at the same time.
C) The smaller mass hits the ground first.
D) No conclusion can be made with the information given.

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Multiple Choice

Q 50Q 50

A baseball catcher throws a ball vertically upward and catches it in the same spot when it returns to his mitt. At what point in the ball's path does it experience zero velocity and non-zero acceleration at the same time?
A) midway on the way up
B) at the top of its trajectory
C) the instant it leaves the catcher's hand
D) the instant before it arrives in the catcher's mitt

Free

Multiple Choice

Q 51Q 51

A baseball is released at rest from the top of the Washington Monument. It hits the ground after falling for 5.0 s. What was the height from which the ball was dropped? (g = 9.8 m/s

^{2}and assume air resistance is negligible) A) 1.5 10^{2}m B) 1.8 10^{2}m C) 1.2 10^{2}m D) 2.1 10^{2}mFree

Multiple Choice

Q 52Q 52

A rock, released at rest from the top of a tower, hits the ground after 2.0 s. What is the speed of the rock as it hits the ground? (g = 9.8 m/s

^{2}and air resistance is negligible) A) 15 m/s B) 20 m/s C) 31 m/s D) 39 m/sFree

Multiple Choice

Q 53Q 53

Omar throws a rock down with speed 2.0 m/s from the top of a tower. The rock hits the ground after 2.0 s. What is the height of the tower? (air resistance is negligible)
A) 20 m
B) 24 m
C) 44 m
D) 63 m

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Multiple Choice

Q 54Q 54

Gwen releases a rock at rest from the top of a 50-m tower. If g = 9.8 m/s

^{2}and air resistance is negligible, what is the speed of the rock as it hits the ground? A) 28 m/s B) 31 m/s C) 56 m/s D) 784 m/sFree

Multiple Choice

Q 55Q 55

John throws a rock down with speed 20 m/s from the top of a 30-m tower. If g = 9.8 m/s

^{2}and air resistance is negligible, what is the rock's speed just as it hits the ground? A) 12 m/s B) 28 m/s C) 31 m/s D) 78 m/sFree

Multiple Choice

Q 56Q 56

Human reaction time is usually about 0.20 s. If your lab partner holds a ruler between your finger and thumb and releases it without warning, how far can you expect the ruler to fall before you catch it? The nearest value is:
A) 4.0 cm.
B) 9.8 cm.
C) 16 cm.
D) 20 cm.

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Multiple Choice

Q 57Q 57

At the top of a cliff 100 m high, Raoul throws a rock upward with velocity 20.0 m/s. How much later should he drop a second rock from rest so both rocks arrive simultaneously at the bottom of the cliff?
A) 5.05 s
B) 3.76 s
C) 2.48 s
D) 1.78 s

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Multiple Choice

Q 58Q 58

Mt. Everest is more than 8000 m high. How fast would an object be moving if it could free fall to sea level after being released from an 8000 m elevation? (Ignore air resistance.)
A) 396 m/s
B) 120 m/s
C) 1200 m/s
D) 12,000 m/s

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Multiple Choice

Q 59Q 59

A water rocket, launched from the ground, rises vertically with acceleration of 20 m/s

^{2}for 1.0 s when it runs out of "fuel." Disregarding air resistance, how high will the rocket rise? A) 15 m B) 30 m C) 61 m D) 102 mFree

Multiple Choice

Q 60Q 60

A parachutist jumps out of an airplane and accelerates with gravity to a maximum velocity of 58.8 m/s in 6.00 seconds. She then pulls the parachute cord and after a 4.00-second constant deceleration, descends at 10.0 m/s for 80.0 seconds, reaching the ground. From what height did the parachutist jump?
A) 914 m
B) 1110 m
C) 1520 m
D) 1750 m

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Multiple Choice

Q 61Q 61

A ball is thrown vertically upwards at 29.4 m/s. For its complete trip (up and back down to the starting position), its average speed is:
A) 14.7 m/s.
B) 9.80 m/s.
C) 4.90 m/s.
D) not given.

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Multiple Choice

Q 62Q 62

The acceleration due to gravity on the Moon's surface is one-sixth that on Earth. What total force would be required to accelerate a 30-kg object at 6.0 m/s

^{2}on the Moon? A) 30 N B) 10 N C) 180 N D) 49 NFree

Multiple Choice

Q 63Q 63

A cart of weight 60 N is accelerated across a level surface at 0.15 m/s

^{2}. What net force acts on the cart? (g = 9.8 m/s^{2}) A) 0.92 N B) 0.31 N C) 3.0 N D) 4.5 NFree

Multiple Choice

Q 64Q 64

A stone is thrown downward from a cliff. Take "up" to be the positive direction. Which of the following statements is true about the stone?
A) The velocity is negative, the acceleration is negative, and the speed is negative.
B) The velocity is positive, the acceleration is negative, and the speed is positive.
C) The velocity is negative, the acceleration is negative, and the speed is positive.
D) The velocity is positive, the acceleration is positive, and the speed is positive.

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Multiple Choice

Q 65Q 65

Two blocks, joined by a string, have masses of 6.0 and 9.0 kg. They rest on a frictionless, horizontal surface. A second string, attached only to the 6.0-kg block, has horizontal force = 45 N applied to it. Both blocks accelerate. Find the tension in the string between the blocks.
A) 18 N
B) 27 N
C) 12 N
D) 9.0 N

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Multiple Choice

Q 66Q 66

Two blocks of masses 20 kg and 8.0 kg are connected together by a light string and rest on a frictionless, level surface. Attached to the 20-kg mass is another light string, which a person uses to pull both blocks horizontally. If the two-block system accelerates at 0.50 m/s

^{2}what is the tension in the connecting string between the blocks? A) 14 N B) 6.0 N C) 10 N D) 4.0 NFree

Multiple Choice

Q 67Q 67

Two blocks of masses 20 kg and 8.0 kg are connected together by a light string and rest on a frictionless, level surface. Attached to the 8.0-kg mass is a second light string, which a person uses to pull both blocks horizontally. If the two-block system accelerates at 1.0 m/s

^{2}, what is the tension in the second string attached to the 8.0-kg mass? A) 14 N B) 6.0 N C) 28 N D) 4.0 NFree

Multiple Choice

Q 68Q 68

Find the tension in an elevator cable if the 1000-kg elevator is ascending with an acceleration of 1.2 m/s

^{2}, upward. A) 11,000 N B) 9800 N C) 8600 N D) 1200 NFree

Multiple Choice

Q 69Q 69

A man of weight is standing on the second floor and is pulling on a rope to lift a box of weight from the floor below. The rope, which is of negligible weight, has tension in it, but the pull of the rope is insufficient to lift the box off the floor. What is the magnitude of the normal force that the second floor exerts on the man in this situation?
A)
B)
C)
D)

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Multiple Choice

Q 70Q 70

A string is attached to the ceiling. At the bottom of the string a rope of the same length as the string is attached. In the rope-string system, which of the following is the position of greatest tension? Assume the rope has more mass per unit length than the string.
A) at the bottom of the rope
B) at the top of the rope where it is attached to the string
C) at the bottom of the string where it is attached to the rope
D) at the top of the string

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Multiple Choice

Q 71Q 71

Assume everyone in the United States consumes one soft drink in an aluminum can every two days. If there are 300 million Americans, how many tons of aluminum need to be recycled each year if each can weighs 1/16 pound, and one ton = 2000 pounds?
A) 750,000 tons
B) 1.5 million tons
C) 1.7 million tons
D) 3 million tons

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Multiple Choice

Q 72Q 72

A physics class in a large lecture hall has 15 students. The total mass of the students is about _____ kg. (You will need to make a reasonable estimate of a missing physical quantity.)
A) 10

^{2}B) 10^{3}C) 10^{4}D) 10^{5}Free

Multiple Choice

Q 73Q 73

A room has 110 ft

^{2}of floor space. What is the approximate volume of the room? (You will need to make a reasonable estimate of a missing physical quantity.) A) 10^{3}ft^{3}B) 10^{4}ft^{3}C) 10^{5}ft^{3}D) 10^{6}ft^{3}Free

Multiple Choice

Q 74Q 74

A cue ball of weight W is falling with an acceleration downward of g/3 and speed v. What is the magnitude of the drag force on the ball at this moment?
A) 0.33W
B) 0.67W
C) 0.11W
D) There is insufficient information to solve this problem.

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Multiple Choice

Q 75Q 75

A cue ball of weight W is falling with acceleration g/2 downward and speed v. What would be the terminal velocity of this ball as it continues to fall?
A) v /2
B) v
C) v
D) 2v

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Multiple Choice

Q 76Q 76

A steel sphere of mass M has a large spherical cavity inside. A second solid steel sphere has mass 4M, but has the same outer radius as the first sphere. If the terminal velocity of the first sphere is v, what would be the terminal velocity of the second sphere?
A) It would also be v since the geometry is the same and the density of steel is the same.
B) It would be v.
C) It would be 2v.
D) It would be 4v.

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Multiple Choice

Q 77Q 77

If the drag force on a car is F at a moderate highway speed v, at what speed would the drag force be doubled?
A) 1.2v
B) 1.4v
C) 1.7v
D) 2.0v

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Multiple Choice