Two spheres P and Q, having radii 8 cm and 2 cm, and of the same surface characteristics are maintained at 127 °C and 527 °C, respectively. The ratio of the radiant powers of P to Q is

Two copper spheres of radii 6 cm and 12 cm, respectively, are suspended in an evacuated enclosure. Each of them is at a temperature of 15 °C above the surroundings. The ratio of their rate of loss of heat is

The peak of the radiation spectrum of a blackbody occurs at 2 µm. Taking Wien’s displacement law constant as 2.9 × $10^{-3}10^\{-3\}$ m.K, the approximate temperature of the blackbody is

The light from the Sun is found to have a maximum intensity near the wavelength of 470 nm. Assuming the surface of the Sun as a blackbody, the temperature of the Sun is [Wien’s constant b = 2.898 × $10^{-3}10^\{-3\}$ m.K]

The amount of energy radiated per unit time by a body does not depend upon the

Two gases exert pressure in the ratio 3 : 2 and their densities are in the ratio 2 : 3. Then the ratio of their rms speeds is

Find the wavelength at which a blackbody radiates maximum energy, if its temperature is 427 °C. [Wien’s constant b = 2.898 × $10^{-3}10^\{-3\}$ m.K]

If the total kinetic energy per unit volume of gas enclosed in a container is E, the pressure exerted by the gas is

Real gases show mark able deviation from that of ideal gas behavior at

Latent heat of ice is