Physics
Heat
Easy
Question
An ideal gas is heated at constant volume until its pressure doubles. Which one of the following statements is correct?
- The mean speed of the molecules doubles.
- The number of molecules doubles.
- The mean square speed of the molecules doubles.
- The number of molecules per unit volume doubles.
The correct answer is: The mean square speed of the molecules doubles.
Assume the mass of the gas is unchanged. Use the kinetic energy theory equation to relate the various factors to the pressure change at constant volume.
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