Thermal Physics Mock Tests

At a given temperature, the ratio of the root-mean-square speeds of O₂ molecules (molar mass 32 g/mol) to H₂ molecules (molar mass 2 g/mol) is:

The RMS speed of molecules of a gas at temperature T and pressure P is v_rms. If the pressure is doubled isothermally, the new RMS speed is:

An ideal gas undergoes an adiabatic compression from volume V to V/2. If the same gas undergoes an isothermal compression from volume V to V/2, comparing the magnitudes of work done, W_adiabatic and W_isothermal:

An ideal gas undergoes an adiabatic compression from volume V to V/2. If the initial pressure is P₀ and γ = 1.5, the final pressure is:

An ideal gas undergoes a cyclic process ABCA as follows: AB is isobaric expansion, BC is isochoric cooling, and CA is isothermal compression. Which statement is true about the net work done over the cycle?

One mole of an ideal diatomic gas (γ = 1.4) undergoes a cyclic process consisting of: (i) isothermal expansion from volume V to 2V at temperature T₀ = 400 K, followed by (ii) isobaric compression back to volume V. The net work done by the gas during the isothermal expansion is:

1 kg of water at 100°C is mixed with 1 kg of water at 0°C in an insulated container. The total entropy change of the system is approximately (take c = 4200 J/kg·K):

A copper block of mass 2 kg at 100 C is placed on a large ice block at 0 C. If the specific heat of copper is 0.4 kJ/kg.K and the latent heat of fusion of ice is 334 kJ/kg, the mass of ice melted is approximately