When an ideal gas is cooled at constant volume until the pressure becomes half of the originalpressure, then the average translational kinetic energy of the gas molecules
Correct answer: B. Becomes half the original.
- A. Remains unchanged.
- B. Becomes half the original.
- C. Becomes twice the original.
- D. Becomes thrice the original.
Explanation
In an ideal gas, the average translational kinetic energy of the molecules is directly proportional to the absolute temperature of the gas. According to the ideal gas law, PV = nRT, where P is pressure, V is volume, T is temperature, and n and R are constants for a given amount of gas. When the gas is cooled at constant volume and the pressure is reduced to half its original value, the temperature must also be reduced to half (since V is constant and nR is constant). Therefore, the average translational kinetic energy, which depends on temperature, also becomes half of its original value. Option B reflects this understanding correctly, while Options A, C, and D do not align with the principles of the ideal gas law.
Report an error
The more specific you are, the faster it gets fixed. A source beats an opinion.
Prefer email? [email protected]
About Thermal Equilibrium and Heat
Thermal equilibrium means that bodies in contact have the same temperature and no net heat flows between them. The topic distinguishes heat from temperature, uses the zeroth law of thermodynamics, and covers heat transfer, specific heat capacity, thermal expansion and the conditions for reaching equilibrium.
Practise Thermodynamics
714 free Thermodynamics MCQs from Physics, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Discussion
Stuck on an option, or know a faster way to get there? Ask or explain it here.
No comments yet. Be the first to explain this one.
Exams that ask Physics questions like this
Physics is on 16 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
More Thermal Equilibrium and Heat questions
The second law of thermodynamics deals with conversion of heat into work and direction of
By reducing the absolute temperature of a black body to half, the total energy radiated will be:
Heat given to a body, which raises its temperature by 1°C is -------------
All Carnot engines have zero efficiency if they are operating between two bodies with
In a thermodynamic system, if there is no change in temperature and internal energy, then the process is called an
The direction of heat flow from one object to another is based on the difference in their