Thermodynamics PYQ — Page 21

Which of the following is more closed to a black body?

Two spheres of the same material have radii $1 \mathrm{~m}$ and $4 \mathrm{~m}$ and temperatures $4000 \mathrm{~K}$ and $2000 \mathrm{~K}$ respectively. The ratio of the energy radiated per second by the first sphere to that by the second is

At what temperature is the r.m.s. velocity of a hydrogen molecule equal to that of an oxygen molecule at $47^{\circ} \mathrm{C}$ ?

Cooking gas containers are kept in a lorry moving with uniform speed. The temperature of the gas molecules inside will

If $\theta_i$, is the inversion temperature, $\theta_n$ is the neutral temperature, $\theta_c$ is the temperature of the cold junction, then

Heat given to a body which raises its temperature by $1^{\circ} \mathrm{C}$ is

1 mole of a gas with $\gamma=7 / 5$ is mixed with 1 mole of a gas with $\gamma=5 / 3$, then the value of $\gamma$ for the resulting mixture is