The number of independent ways by which a dynamic system can move… - Vidyadip

Question

The number of independent ways by which a dynamic system can move, without violating any constraint imposed on it, is called the number of degrees of freedom. According to the law of equipartition of energy, for any dynamic system in thermal equilibrium, the total energy for the system is equally divided among the degree of freedom.

1. If gas has $n$ degree of freedom, the ratio of specific heat is:
(a) $-2 n$ (b) 2 n (c) $1+2 / n$ (d) $1-2 / n$
2. The kinetic energy, due to translational motion, of most of the molecules of an ideal gas at absolute temperature T , is:
(a) $kT ^3$ (b) $kT ^2$ (c) kT (d) $k / T$
3. The mean free path is the:
(a) length of the container that contains the gas
(b) mean of the square of the average distance between two successive collisions
(c) the average distance covered by a molecule between two successive collisions
(d) height of the container that contains the gas
4.The law of equipartition of energy is applicable to the system whose constituents are:
(a) in non random motion
(b) in random motion
(c) in orderly motion
(d) in rest
OR
Thermochemical calorie is equal to
(a) 41.48 joule (b) 4.148 joule (c) 4148 joule (d) 414.8 joule

✓

Answer

1. (c) $1+2 / n$
Explanation: $1+2 / n$
2. (c) kT
Explanation: kT
3. (c) the average distance covered by a molecule between two successive collisions
Explanation: the average distance covered by a molecule between two successive collisions
4. (b) in random motion
Explanation: in random motion
OR
(b) 4.148 joule
Explanation: 4.148 joule

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