Question

For a constant volume gas thermometer select the correct statement.

(a) It doesn’t use mercury for pressure measurement

(b) We actually measure the pressure at constant volume and the scale is calibrated to give the temperature reading

(c) Any high density gas can be used

(d) Pressure ∝ Temp^2

I had been asked this question in an interview for internship.

My question is based upon Thermal Properties of Matter topic in chapter Thermal Properties of Matter of Physics – Class 11

Answer 1

Correct option is (b) We actually measure the pressure at constant volume and the scale is calibrated to give the temperature reading

Easy explanation: A constant volume gas thermometer has a mercury manometer connected to a gas bulb. With increase in temperature of the bulb, its volume is kept constant by external methods and the pressure of gas increases.                                                                                                                                                   The temperature scale is defined as a function of this pressure.                                                                                       (T = kP, where k is a constant).