Specific heats for an incompressible substance

In summary, specific heats at constant pressure and volume are the same for incompressible substances because at constant volume, there is no PV work possible, so all heat goes into increasing the energy of the molecules. At constant pressure, some heat is lost to the surroundings as work, requiring more heat to achieve the same temperature change. For incompressible substances, no PV work is possible, making the specific heats at constant pressure and volume equal.
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KOUSIK
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why specific heats at constant pressure and volume are the same for an incompressible substance?
 
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KOUSIK said:
why specific heats at constant pressure and volume are the same for an incompressible substance?

The reason that they are very different fo things like ideal gases is that with a gas at constant volume, there is no PV work possible. All of the heat going into the gas goes to increasing the energy of the gas molecules. At constant pressure, as you heat the gas, the gas will expand against that pressure -- doing PV work. Some of the heat energy that you added to the gas went out of the gas into the surroundings as work. More heat needs to be supplied to get the same change in temperature.

For incompressible materials, is this possible? Can the substance do any PV work?
 
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thank u
 

Related to Specific heats for an incompressible substance

1. What is a specific heat for an incompressible substance?

A specific heat for an incompressible substance is a measure of the amount of heat energy required to raise the temperature of a unit mass of the substance by one degree.

2. How is specific heat for an incompressible substance different from specific heat for a compressible substance?

Incompressible substances, such as liquids, have a constant density and therefore their specific heat remains constant regardless of changes in temperature or pressure. Compressible substances, such as gases, have varying densities and therefore their specific heat can change with changes in temperature or pressure.

3. What factors can affect the specific heat of an incompressible substance?

The specific heat of an incompressible substance can be affected by changes in temperature, pressure, and composition of the substance. It can also be influenced by external factors such as impurities or the presence of other substances.

4. How is specific heat measured for an incompressible substance?

Specific heat is typically measured using calorimetry, which involves measuring the heat absorbed or released by a substance as it undergoes a temperature change. This can be done using specialized equipment such as a bomb calorimeter or a differential scanning calorimeter.

5. Why is understanding the specific heat of incompressible substances important in scientific research?

Understanding the specific heat of incompressible substances is important in various fields of scientific research, such as thermodynamics, material science, and engineering. It allows for accurate calculations and predictions of heat transfer and energy usage, which are essential in the design and optimization of processes and materials.

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