Question

Why can any low density gas be used in a constant volume gas thermometer?

(a) All low density gases show the same expansion behaviour

(b) They are easy to handle

(c) Their pressure variation is proportional to square of the change in temperature

(d) The given statement is not true

The question was posed to me during an interview.

Origin of the question is Thermal Properties of Matter in portion Thermal Properties of Matter of Physics – Class 11

Answer 1

Correct answer is (a) All low density gases show the same expansion behaviour

Explanation: It has been experimentally shown that low density gases show similar expansion behaviour. If we keep the gas’s volume constant pressure increases monotonically with increasing temperature. Hence, we can use any low density gas for a constant volume gas thermometer.