1. An amusement park ride has a diameter of 16 meters and revolves at 15 rpm (revolutions per minute). How fast is a rider moving if she sits at the outermost part of the ride?

A. 29.4 m/s
B. 1.07 m/s <<<<
C. 225 m/s
D. 12.56 m/s
E. 9.8 m/s

2. A police officer spots a speeding car traveling at 20 m/s (approximately 44 mph) as it passes. The officer immediately starts to drive, accelerating from rest at a rate of 5 m/s². How far will the officer have to drive before catching up to the speeding car?

A. 100 m
B. 80 m
C. 500 m
D. 16 m <<<<<
E. 160 m

3. While rising vertically at 10 m/s, a helicopter passenger falls out the door. Fortunately, he has a rope tied to his harness so he can be retrieved. After 2.5 seconds, how much rope has been pulled out of the helicopter?

30.625 m <<<<<
25 m
26.625 m
1.625 m
Cannot be determined with the given information

4. Which of the following statements are always true for inelastic collisions?

I. System total mechanical energy is not conserved.
II. System momentum is conserved.
III. The objects stick together.

A. I
B. II
C. I and II
D. I and III
E. I, II, and III <<<<<

5. How much total mechanical work does a weight lifter do in 10 repetitions of lifting (and lowering) 200 kg to a height of 1.0 m?

A. Zero
B. 200 J
C. 2000 J
D. 19,600 J
E. 39,200 J <<<<<

6. On a curved roadway of radius 100 m, the suggested speed limit is 35 mph (approximately 16 m/s). What must the coefficient of friction be between a car’s tires and the road for the car to safely negotiate the curve at the posted speed?

A. 0.72 <<<<<
B. 0.51
C. 0.26
D. 0.40
E. 0.13


7. An ideal gas is held in a rigid container whose volume is 0.25 m³. It is heated from 100ºC, where it is at a pressure of 2 x 105 Pa, to a final temperature of 250ºC. What is the change in pressure of the gas?

A. 10 • 105 Pa
B. 2.5 • 105 Pa
C. 5.0 • 105 Pa
D. .80 • 105 Pa <<<<
E. 150 • 105 Pa

8. A piece of solid lead weighing 6.5 kg at 327ºC (its melting point) receives 150,000 joules of heat. In what state is the lead after this occurs? The latent heat of fusion for lead is 23,200 J/kg.

A. 6.5 kg of solid lead at 327ºC
B. 6.5 kg of solid lead at a higher temperature
C. 6.5 kg of melted lead at 327ºC
D. Some of it is melted lead, and some of it stays solid.
E. 6.5 kg of melted lead at a higher temperature <<<<<

1. Circumference=Pi*D=3.14 * 16=50.27 m.

V = 15rev/60s * 50.27m/rev = 12.56 m/s.

2. 0.5*5*t^2 = 20*t
2.5t^2 - 20t = 0
t = 8 s. (Use Quad. Formula).
d = 20 * 8 = 160 m.

3. d = Yo*t + 4.9*t^2
d = -10*2.5 + 4.9*2.5^2 =

4. 1.

5. Work = !0*F*d = 10*(mg)*d
Work = 10*(1960)*1 = 19,600 J.

Are all the other correct?

Are the others correct Henry or anyone else?