The perfect gas equation for 4g of hydrogen gas is

If the temperature of the Sun gets doubled, the rate of energy received on the Earth will increase by a factor of

If the rms velocity of hydrogen gas at a certain temperature is c, then the rms velocity of oxygen gas at the same temperature is

The temperature of the water of a pond is 0$$^\circ$$C while that of the surrounding atmosphere is $$-$$20$$^\circ$$C. If the density of ice is $$\rho$$, coefficient of thermal conductivity is k and latent heat of melting is L, then the thickness Z of ice layer formed increases as a function of time t is