A 2.00-kg ball has zero potential and kinetic energy. Maria drops the ball into a 20.0-m deep well. After the ball comes to a stop in the mud, the sum of its potential and kinetic energy is:
a. 392 J.
c. 784 J.
b. -392 J.
d. zero.
[Ques. 2] Three Carnot engines operate between temperature reservoirs as follows: Engine A: Th = 1300 K, Tc = 1000 K; Engine B: Th = 1000 K, Tc = 700 K; Engine C: Th = 500 K, Tc = 350 K. Which two engines have the same thermal efficiency?
a. A and B
b. B and C
c. A and C
d. No two have the same thermal efficiency.
[Ques. 3] A 2.00 kg-ball has zero kinetic and potential energy. Ernie drops the ball into a 10.0-m deep well. Just before the ball hits the bottom, the sum of its kinetic and potential energy is:
a. zero.
c. -196 J.
b. 196 J.
d. 392 J.
[Ques. 4] Consider a Carnot cycle starting at the state of highest pressure and smallest volume. Call the isothermal expansion from this state step 1, the adiabatic expansion which follows step 2, the isothermal compression that then follows step 3, and the adiabatic compression which returns the system to the initial state step 4 . In which steps does the internal energy of the system increase?
a. 1 and 2
c. 1 and 3
b. 3 and 4
d. 2 and 4
[Ques. 5] A hill is 200 m long and makes an angle of 12 with the horizontal. As a 50-kg jogger runs up the hill, how much work does gravity do on the jogger?
a. 98,000 J
c. 20,000 J
b. -20,000 J
d. zero
[Ques. 6] In an isochoric process where the pressure increases from to , does the internal energy of the system increase or decrease and does the temperature increase or decrease?
a. The internal energy increases and the temperature decreases.
b. The internal energy increases and the temperature increases.
c. The internal energy decreases and the temperature decreases.
d. The internal energy decreases and the temperature increases.
[Ques. 7] A simple pendulum, 2.0 m in length, is released by a push when the support string is at an angle of 25 from the vertical. If the initial speed of the suspended mass is 3.0 m/s when at the release point, to what maximum angle will it move in the second half of its swing?
a. 36
c. 19
b. 30
d. 47
[Ques. 8] A thermodynamic process that happens very quickly tends to be:
a. isobaric. c. isovolumetric. b. isothermal.
d. adiabatic.
[Ques. 9] A simple pendulum, 2.0 m in length, is released with a push when the support string is at an angle of 25 from the vertical. If the initial speed of the suspended mass is 2.0 m/s when at the release point, what is its speed at the bottom of the swing? (g = 9.8 m/s2)
a. 2.3 m/s
c. 2.8 m/s
b. 2.6 m/s
d. 0.5 m/s
[Ques. 10] A cylinder containing an ideal gas has a volume of 3.0 m3 and a pressure of 1.0 105 Pa at a temperature of 300 K. The cylinder is placed against a metal block that is maintained at 900 K, and the gas expands as the pressure remains constant until the temperature of the gas reaches 900 K. The change in internal energy of the gas is +6.0 105 J. How much heat did the gas absorb?
a. 0
c. 12 105 J
b. 6.0 105 J
d. 9.0 105 J
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