A spherical blackbody of 12 cm radius used to emit 540 w thermal energy at 500 k temperature.. If the radius is halved and temperature is doubled then what will be the radiant energy?

A spherical black body of radius 12 cm radiates 450 W power at 500 K. If the radius is reduced to half and temperature is doubled. find the power- radiated in watt.

A spherical blackbody of radius 12 cm at 5000 K temperature emits 540 watt thermal power. Find out the emitted power if its radius being half & temperature being doubled.

Consider a blackbody radiation in a cubical box at absolute temperature T. If the length of each side of the box is doubled and the temperature of the walls of the box and that of the radiation is halved, then the total energy

(i) The pressure and temperature of 0.8 g of He gas are 1 atm and 298 K respectively. If 400 J of heat is applied to the gas at constant volume, what will be change in internal energy and the final temperature of the gas ? (ii) If the same amount of heat is applied to the gas at constant pressure, then what will be the change in internal energy and the final temperature of the gas ? For both the cases, assume He gas behaves ideally and its C_(V)=(3)/(2)R .

For an ideal gas, C_(V)=(3)/(2)R . (a) What will be the change in internal energy (DeltaU) of 1 mole of an ideal gas if its temperature is increased by 4K at constant volume ? What would be DeltaU if the temperature of this gas is increased by the same amount of constant pressure? keeping pressure constant if the temperature of that same amount of gas is increased by 4K then what will be the change in internal energy (DeltaU) of that gas? (c) give reason for different values of DeltaU and DeltaH ?

At what temperature the average kinetic energy of the molecules of a perfect gas be doubled than that at 20^@C ?