A black metal foil is warmed by radiation from a small sphere at temperature `T` and at a distance d it is found that the power received by the foil is `P` If both the temperature and the distance are doubled the power received by the foil will be .

A surface at temperature T_(0)K receives power P by radiation from a small sphere at temperature T ltT_(0) and at a distance d. If both T and d are doubled the power received by the surface will become .

The power P is received by a surface at temperature T_(0)K from a small sphere at temperature

The radiation power from a source at temperature T and2m away is 2W//m^(2) . If the temperature of the source increases by 100% the radiation power at a distance 4m from the source will increase by:

The surface temperature of the sun is T_(0) and it is at average distance d from a planet. The radius of the sun is R . The temperature at which planet radiates the energy is

A spherical black body with a radius of 12 cm radiates 450 watt power at 500 K. If the radius were halved and the temperature doubled, the power radiated in watt would be

Radiation from a black body at the thermodynamic temperature T_(1) is measured by a small detector at distance d_(1) from it. When the temperature is increased to T_(2) and the distance to d_(2) , the power received by the detector is unchanged. What is the ratio d_(2)//d_(1) ?

A spherical black body with radius 12 cm radiates 640 w power at 500 K. If the radius is halved and the temperature doubled, the power radiated in watts would be

A spherical black body with radius 12 cm radiates 450 W power at 500 K. If the radius is halved and temperature is doubled, the power radiated in watt would be

A spherical black body with a radius of 20 cm radiates 440 W power at 500 K. If the radius were halved and the temperature doubled, the power radiated in watt would be