26.

Imagine that you are standing on a scale in an elevator. The scale shows that your apparent weight is greater than your actual weight. Describe two situations that could achieve this outcome.

27.

Liam is rowing a kayak westward with an average force of

22.7

N. The wind is blowing directly east, with an average force of

17.4

N. What is the net force on the canoe?

	40.1 N west
	5.3 N east
	5.3 N west
	40.1 N east

28.

Stephanie is pushing a laboratory cart into the storage closet. If she applies a

63

N force for a period of

2.2

seconds, how much will the cart's momentum change during that period?

	140 kg*m/s
	29 kg*m/s
	260 kg*m/s
	63 kg*m/s

29.

A basketball player jumps into the air, and shoots the

505

g basketball directly eastward with a force of

14.9

N. What is the force that the ball exerts on the player?

	14.9 N to the west
	14.9 N to the east
	7.52 N to the west
	7.52 N to the east

30.

Why is physics often considered to be the fundamental science?

31.

The planet Mars has a mass of

6.42

10

23

kg, and a radius of

3390

km. How much would an astroid with a mass of

570

kg weigh on the surface of Mars?

	11 , 400 N
	2130 N
	15 , 800 N
	1750 N

32.

Lars is moving his washing machine, to do some maintenance. The washing machine has a mass of

85

kg, and the coefficient of friction between the machine and the ground is

0.551

. When the machine is sliding, what is the magnitude of the force of friction?

	460 N
	150 N
	47 N
	830 N

33.

Phoebe is packing up her items to move. One box has a weight of

410

N. The base of the box has an area of

0.45

m

2

. What is the pressure exerted by the box on the floor?

	390 Pa
	180 Pa
	910 Pa
	410 Pa

34.

A

2800

kg truck is driving down the road. If the truck is driving at a speed of

24.7

m/s, how much kinetic energy does the truck have?

	8.54 10 5 J
	3.46 10 4 J
	1.04 10 6 J
	5.91 10 5 J

35.

Jeremy uses a tennis ball launcher to help him practice. He notices that when he leaves the tennis ball launcher on the wheeled cart, it moves backward every time it fires a ball forward. How is this phenomenon explained by Newton's third law?

36.

A bird is flying

44.5

meters above the ground, holding a stick with its feet. If the bird were to drop the stick, how long would it take for the stick to reach the ground below?

	9.07 s
	2.68 s
	4.91 s
	3.01 s

37.

Leslie is speeding up to merge with traffic. When she begins to speed up, she has a velocity of

7.0

m/s west. When she merges with traffic

7.0

seconds later, she is traveling

23

m/s. Assuming east to be the positive direction, what is Leslie's average rate of acceleration during this period?

	1.9 m/s 2
	2.3 m/s 2
	2.3 m/s 2
	1.9 m/s

38.

The International Space Station (ISS) experiences something called orbital decay, causing the ISS to get

90

m closer to Earth every hour. What effect does orbital decay have on the velocity and orbital velocity of the ISS?

39.

Why is it helpful to break vectors into their horizontal and vertical components before adding vectors?

40.

Rhea is driving north in a straight line. After driving for

2.4

kilometers, she turns west, and drives for

3.1

km. At the end of her drive, what is the magnitude of her displacement vector?

	2.3 km
	5.5 km
	2.8 km
	3.9 km

41.

A train is traveling at a constant speed along a track. As the train goes around a turn, is there a net force acting on the train? Why or why not?

42.

If an object had a positive acceleration, what would the graph of the object's velocity versus time look like?

43.

Shiela is competes in the long jump event. If she jumps at an angle

22.7

above horizontal, and with an initial velocity of

9.44

m/s, what will her range be?

	6.46 m
	8.04 m
	7.22 m
	5.10 m

44.

Sheldon is pulling a box of athletic equipment across the floor of the school gym. The box has a mass of

51.9

kg. As he pulls, the box accelerates at a rate of

0.355

m/s

2

. How much force is Sheldon exerting on the box?

	93.0 N
	27.7 N
	18.4 N
	146 N

45.

Astronomers are constantly looking for Earth-like planets: planets with similar gravity and temperatures as Earth. In order to have the exact same gravity as Earth, must a planet have the same mass and radius? Explain your answer.

46.

Jonah places a

9.05

kg box on a

21

ramp. The box accelerates at a rate of

0.44

m/s

2

. What is the coefficient of kinetic friction between the box and the ramp?

	0.34
	0.54
	0.21

47.

Thalia is designing a compound machine for her physics class. She wants to set up a system so that she can press down on a lever with

10

N, over a distance of

0.1

m, and the output of the machine will be a

1

N force exerted over

3

m. Is this possible to develop? Justify your answer.

48.

If someone were to throw an object vertically, and catch it as it returned back down, describe how the velocity vector of this object changes over this period.

9.

Jody is spinning a

635

g weight tied to a string over her head. The string is

0.88

m long, and the weight is moving with a speed of

5.35

m/s. What is the centripetal force pulling the weight inward?

	3.86 N
	5.68 N
	20.6 N
	18.7 N

50.

An airplanes engine is able to produce a fixed maximum force. Why does having fewer passengers aboard allow the airplane to reach takeoff speed more quickly?