Two spheres of the same materials have radii 1 m and 4 m and temperatures 4000 K and 2000 K resectively the energy radiated per second by the first sphere is

Explanation

Energy radiated per second `propAT^(4)prop(R^(2))T^(4)`
`(E_(1))/(E_(2))=((1)/(4))^(2)((4000)/(2000))^(4)=1orE_(1)=E_(2)`