Short Answer
12.1 Zeroth Law of Thermodynamics: Thermal Equilibrium
What does green energy development entail?
- Green energy involves finding new ways to harness clean and renewable alternative energy sources.
- Green energy involves finding new ways to conserve alternative energy sources.
- Green energy involves decreasing the efficiency of nonrenewable energy resources.
- Green energy involves finding new ways to harness nonrenewable energy resources.
Why are the sun and Earth not in thermal equilibrium?
- The mass of the sun is much greater than the mass of Earth.
- There is a vast amount of empty space between the sun and Earth.
- The diameter of the sun is much greater than the diameter of Earth.
- The sun is in thermal contact with Earth.
12.2 First law of Thermodynamics: Thermal Energy and Work
If a fixed quantity of an ideal gas is held at a constant volume, which variable relates to pressure, and what is that relation?
- Temperature; inverse proportionality
- Temperature, direct proportionality to square root
- Temperature; direct proportionality
- Temperature; direct proportionality to square
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when the pressure of the gas is variable
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when the pressure of the gas is constant
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when the mass of the gas is variable
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when the mass of the gas is constant
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pressure acting over the change in depth
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pressure acting over the change in temperature
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temperature acting over the change in volume
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pressure acting over the change in volume
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the work done on the system
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the work done by the system
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the heat into the system
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the heat out of the system
By convention, if Q is positive, what is the direction in which heat transfers energy with regard to the system?
- The direction of the heat transfer of energy depends on the changes in W, regardless of the sign of Q.
- The direction of Q cannot be determined from just the sign of Q.
- The direction of net heat transfer of energy will be out of the system.
- The direction of net heat transfer of energy will be into the system.
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It is the sum of all energy transfers by heat into the system.
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It is the product of all energy transfers by heat into the system.
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It is the sum of all energy transfers by heat into and out of the system.
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It is the product of all energy transfers by heat into and out of the system.
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{-190}\,\text{J} ; this would change if heat added energy after the work was done
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190\,\text{J}; this would change if heat added energy after the work was done
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{-190}\,\text{J}; this would not change even if heat added energy after the work was done
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190\,\text{J}; this would not change even if heat added energy after the work was done
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10\,\text{J}; the change in internal energy would be same even if the heat added the energy at once
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30\,\text{J}; the change in internal energy would be same even if the heat added the energy at once
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10\,\text{J}; the change in internal energy would be more if the heat added the energy at once
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30\,\text{J}; the change in internal energy would be more if the heat added the energy at once
12.3 Second Law of Thermodynamics: Entropy
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Entropy depends on the change of phase of a system, but not on any other state conditions.
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Entropy does not depend on how the final state is reached from the initial state.
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Entropy is least when the path between the initial state and the final state is the shortest.
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Entropy is least when the path between the initial state and the final state is the longest.
Which sort of thermal energy do molecules in a solid possess?
- electric potential energy
- gravitational potential energy
- translational kinetic energy
- vibrational kinetic energy
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the first law of thermodynamics
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the second law of thermodynamics
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the third law of thermodynamics
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the zeroth law of thermodynamics
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by doing work on the system
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by having work done by the system
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by increasing the specific heat of the cold body
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by increasing the specific heat of the hot body
What is the change in entropy caused by melting 5.00 kg of ice at 0 °C ?
- 0 J/K
- 6.11×103 J/K
- 6.11×104 J/K
- ∞J/K
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1.1 \times 10^{1}\,\text{J}
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1.1 \times 10^{2}\,\text{J}
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1.4 \times 10^{3}\,\text{J}
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1.4 \times 10^{4}\,\text{J}
12.4 Applications of Thermodynamics: Heat Engines, Heat Pumps, and Refrigerators
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The evaporator converts gaseous refrigerant into liquid.
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The evaporator converts solid refrigerant into liquid.
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The evaporator converts solid refrigerant into gas.
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The evaporator converts liquid refrigerant into gas.
Which component of an air conditioner converts gas into liquid?
- the condenser
- the compressor
- the evaporator
- the thermostat
What is one example for which calculating thermal efficiency is of interest?
- A wind turbine
- An electric pump
- A bicycle
- A car engine
How is the efficiency of a refrigerator or heat pump expressed?
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\frac{Q_{h} - Q_{c}}{Q_{h}}
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1 - \frac{Q_{h} - Q_{c}}{Q_{h}}
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\frac{W - Q_{c}}{Q_{h}}
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1 + \frac{W - Q_{c}}{Q_{h}}
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percentage efficiency = \left(Eff + 100\right)\%
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percentage efficiency = \frac{Eff}{100}\%
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percentage efficiency = \left(Eff - 100\right)\%
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percentage efficiency = Eff \times 100\,\%