16.

The wheel of a car is spinning with a period of

0.138

s. If the wheel has a radius of

0.343

m, what is the velocity of a point on the edge of the wheel?

	9.15 m/s
	19.2 m/s
	13.4 m/s
	15.6m/s

17.

Havilah is pushing a shopping cart with a force of

19.9

N, at angle of

16.1

downward from the horizontal. If she pushes the cart 9.55 m, how much work has she done on it?

	165 J
	183 J
	190 J
	195 J

18.

At sea level, the air pressure is

101

,

325

Pa. How much force is the air at sea level exerting on an area of

4.41

m

2

?

	4.47 10 5 N
	7.68 10 4 N
	1.29 10 5 N
	2.3 10 4 N

19.

Florence is spinning a

770

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

0.94

m long, and the weight is moving with a speed of 4.24 m/s. What is the centripetal force pulling the weight inward?

	20.6 N
	19.7 N
	11.0 N
	14.7 N

20.Earth's orbit is nearly circular. If, however, Earth's orbit were more elongated and elliptical, what other effects would that have on Earth's orbit?

21.

A certain type of centrifuge spins specimens by attaching them to a

0.4

m cable. If the specimen being spun has a mass of

250

g, and the cable is designed to fail at a force greater than

660

N, what is the maximum velocity the specimen can reach?

	24.2 m/s
	29.1 m/s
	32.5 m/s
	16.0 m/s

22.

In a circus stunt sometimes called a "globe of death," a motorcyclist rides inside of a spherical cage. When they are traveling fast enough, they exhibit uniform circular motion. What is causing the centripetal force that keeps them in uniform circular motion?

23.

An Olympic-size swimming pool has a length of

50.0

m, a width of

25.0

m, and contains

2.5

10

6

kg of water. What is the pressure that the water exerts on the floor of the pool?

	2000 Pa
	7790 Pa
	8450 Pa
	19 , 600 Pa

24.

A carnival ride spins riders in a circle. The ride operator does not want the centripetal acceleration on the ride to exceed

19.62

m/s

2

. If the radius of the ride is

5.50

m, what is the maximum speed the riders can achieve, and stay under the acceleration limit?

	25.1 m/s
	3.57 m/s
	10.4 m/s
	108 m/s

25.

Lindsay is in an airplane, preparing to skydive. Lindsay has a mass of

71.1

kg, and the airplane is flying at an altitude of

3620

m above the ground. Before she jumps from the airplane, how much gravitational potential energy does he have?

	2.52 10 6 J
	6.44 10 5 J
	2.57 10 5 J
	1.90 10 6 J

26.

Robert is riding his skateboard around a skate park. At the top of one feature, he has

475

J of kinetic energy, and

2240

J of gravitational potential energy. Ignoring friction, how much total energy will Robert have when he is at the bottom of the feature.

	2715 J
	2240 J
	475 J
	1765 J

27.

On a certain planet, a

4950

kg rock weighs

22

,

030

N. If this planet has a radius of

4200

km, what is the mass of the planet?

	1.92 10 25 kg
	1.18 10 24 kg
	4.51 10 24 kg
	3.06 10 25 kg

28.

One of Saturn's moons orbits with a period of approximately

2.7

days. If Saturn has a mass of

5.68

10

26

kg, then what is the orbital radius of this moon?

	8.76 10 10 m
	5.23 10 25 m
	6.29 10 16 m
	3.74 10 8 m

28.

One of Saturn's moons orbits with a period of approximately

2.7

days. If Saturn has a mass of

5.68

10

26

kg, then what is the orbital radius of this moon?

	8.76 10 10 m
	5.23 10 25 m
	6.29 10 16 m
	3.74 10 8 m

29.

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

340

N. The base of the box is

0.36

m

2

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

	120 Pa
	360 Pa
	340 Pa
	940 Pa

30.

A

815

kg roller coaster cart is at rest at the top of a

51.2

m hill. When the cart reaches the bottom of the hill, how quickly will it be moving?

	21.5 m/s
	30.0 m/s
	31.7 m/s
	28.2 m/s