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.

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 air bubbles is rising from the depth of a lake when pressure is P atm and temperature is T K what is the percentage increase in its radius when it comes to the surface of a lake. (Assume : temperature and pressure at the surface to be respectively 2T K and P/4 )

A circular disc of radius 3 cm is being heated. Due to expansion, its radius increases at the rate of 0.05 cm/s. Find the rate at which its area is increasing when radius is 3.2 cm.

A balloon, which always remains spherical on inflation, is being inflated by pumping in 900 cubic centimetres of gas per second. Find the rate at which the radius of the balloon increases when the radius is 15 cm.