Gases possess___________________?
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Answer: B. two values of specific heat
Explanation
Gases can be heated at either constant volume or constant pressure conditions. Each heating condition requires a distinct amount of energy to raise temperature. Therefore, gases inherently possess two unique specific heat capacity values. Specific heat is the amount of heat needed to raise unit mass by one degree. Cp represents specific heat at constant pressure while Cv represents constant volume. For ideal gases, Cp is always greater than Cv by the gas constant R.
Thermodynamic calculations for gas turbines require both specific heat values. Internal combustion engine cycles use specific heat ratios to determine thermal efficiency. Chemical engineers use these values to design heat exchangers handling reactive gases. Option A is wrong because a single specific heat applies only to incompressible liquids. Option C incorrectly suggests the existence of three distinct specific heat values. Option D is false because gases certainly possess measurable specific heat capacities.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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