Thermodynamics

101. The energy of molecular motion appears as

1. heat
2. potential energy
3. surface tension
4. friction
5. increase in pressure.

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102. The first law of thermodynamics is the law of

1. conservation of mass
2. conservation of energy
3. conservation of momentum
4. conservation of heat
5. conservation of temperature.

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103. The following cycle is used for air craft refrigeration

1. Brayton cycle
2. Joule cycle
3. Carnot cycle
4. Bell-Coleman cycle
5. Reversed-Brayton cycle.

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104. The ideal efficiency of a Brayton cycle with regeneration, with increase in pressure ratio will

1. increase
2. decrease
3. remain unchanged
4. increase/decrease depending on ap-plication
5. unpredictable. "

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105. The ideal efficiency of a Brayton cycle without regeneration with increase ni pressure ratio will

1. increase
2. decrease
3. remain unchanged
4. increase/decrease depending on application
5. unpredictable.

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106. The index of compression n tends to reach ratio of specific heats y when

1. flow is uniform and steady
2. process is isentropic
3. process is isothermal
4. process is isentropic and specific heat does not change with temperature
5. process is isentropic and specific heat changes with temperature.

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107. The more effective way of increasing efficiency of Carnot engine is to

1. increase higher temperature
2. decrease higher temperature
3. increase lower temperature
4. decrease lower temperature
5. keep lower temperature constant.

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108. The pressure'of a gas in terms of its mean kinetic energy per unit volume E is equal to

1. E/3
2. E/2
3. 3E/4
4. 2E/3
5. 5E/4.

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109. The ratio of two specific heats of air is equal to

1. 0.17
2. 0.24
3. 0.1
4. 1.41
5. 2.71.

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110. The same volume of all gases would represent their

1. densities
2. specific weights
3. molecular weights
4. gas characteristic constants
5. specific gravities.

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