Practice Questions
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| 1. |
1
kg of cold water at 5ºC is added to a container of 5 kg of hot water
at 65º C. What is the final temperature of the water when it arrives
at thermal equilibrium? |
| (A) |
10ºC |
| (B) |
15ºC |
| (C) |
35ºC |
| (D) |
55ºC |
| (E) |
60ºC |
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| 2. |
Which
of the following properties must be known in order to calculate
the amount of heat needed to melt 1.0 kg of ice at 0ºC? |
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I. The specific heat of water
II. The latent heat of fusion for water
III. The density of water
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| (A) |
I only |
| (B) |
I and II only |
| (C) |
I, II, and III |
| (D) |
II only |
| (E) |
I and III only |
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| 3. |
Engineers
design city sidewalks using blocks of asphalt separated by a small
gap to prevent them from cracking. Which of the following laws best
explains this practice? |
| (A) |
The Zeroth Law of Thermodynamics |
| (B) |
The First Law of Thermodynamics |
| (C) |
The Second Law of Thermodynamics |
| (D) |
The law of thermal expansion |
| (E) |
Conservation of charge |
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| 4. |
Which
of the following is an example of convection? |
| (A) |
The heat of the sun warming our planet |
| (B) |
The heat from an electric stove warming a frying pan |
| (C) |
Ice cubes cooling a drink |
| (D) |
A microwave oven cooking a meal |
| (E) |
An overhead fan cooling a room |
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| 5. |
An
ideal gas is enclosed in a sealed container. Upon heating, which
property of the gas does not change? |
| (A) |
Volume |
| (B) |
Pressure |
| (C) |
The average speed of the molecules |
| (D) |
The rate of collisions of the molecules with each other |
| (E) |
The rate of collisions of the molecules with the walls
of the container |
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| 6. |
A
box contains two compartments of equal volume separated by a divider.
The two compartments each contain a random sample of n moles
of a certain gas, but the pressure in compartment A is
twice the pressure in compartment B. Which of the
following statements is true? |
| (A) |
The temperature in A is twice the temperature
in B |
| (B) |
The temperature in B is twice the temperature
in A |
| (C) |
The value of the ideal gas constant, R,
in A is twice the value of R in B |
| (D) |
The temperature in A is four times as
great as the temperature in B |
| (E) |
The gas in A is a heavier isotope than
the gas in B |
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| 7. |
An
ideal gas is heated in a closed container at constant volume. Which
of the following properties of the gas increases as the gas is heated? |
| (A) |
The atomic mass of the atoms in the molecules |
| (B) |
The number of molecules |
| (C) |
The density of the gas |
| (D) |
The pressure exerted by the molecules on the walls of the
container |
| (E) |
The average space between the molecules |
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| 8. |
24
J of heat are added to a gas in a container, and then the gas does
6 J of work on the walls of the container. What is the change in
internal energy for the gas? |
| (A) |
–30 J |
| (B) |
–18 J |
| (C) |
4 J |
| (D) |
18 J |
| (E) |
30 J |
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| 9. |
When
water freezes, its molecules take on a more structured order. Why
doesn’t this contradict the Second Law of Thermodynamics? |
| (A) |
Because the density of the water is decreasing |
| (B) |
Because the water is gaining entropy as it goes from liquid
to solid state |
| (C) |
Because the water’s internal energy is decreasing |
| (D) |
Because the surroundings are losing entropy |
| (E) |
Because the surroundings are gaining entropy |
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| 10. |
A
heat engine produces 100 J of heat, does 30 J of work, and emits
70 J into a cold reservoir. What is the efficiency of the heat engine? |
| (A) |
100% |
| (B) |
70% |
| (C) |
42% |
| (D) |
40% |
| (E) |
30% |
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