A hot metallic sphere of radius r radiates heat. It's rate of cooling is

A spherical black body of radius n radiates power p and its rate of cooling is R. then.

A spherical black body of radius n radiates power p and its rate of cooling is R. then.

A spherical solid blakc body of radius 'r' radiates power 'H' and its rate of cooling is 'C'. If density is constant then which of the following is/are true.

A spherical solid blakc body of radius 'r' radiates power 'H' and its rate of cooling is 'C'. If density is constant then which of the following is/are true.

A very thin metallic shell of radius r is heated to temperature T and then allowed to cool. The rate of cooling of shell is proportional to

A very thin metallic shell of radius r is heated to temperature T and then allowed to cool. The rate of cooling of shell is proportional to

A metallic sphere of radius ‘r’ is melted and recast into the shape of solid cylinder of radius ‘r’, the height of the cylinder is

The rate of change of surface area of a sphere of radius r when the radius is increasing at the rate of 2 cm/sec is proportional to