According to the question, Area of both bodies A and B=A Temperature of body A=27∘C=27+273K Temperature of body B=177∘C=177+273K Now, by Stefan-Boltzmann law, thermal energy radiated per second by a body Q=σAT4 where, A = Area T= temperature and σ= Stefan-Boltzmam's constant So, the ratio of thermal energy radiated per second by A to that by B is
Q1
Q2
=
σA
σA
(
T1
T2
)4 Now,
Q1
Q2
=(
T1
T2
)4
Q1
Q2
=(
273+27
273+177
)4
Q1
Q2
=(
300
450
)4
Q
Q2
=(
2
3
)4=(
16
81
) Ratio of thermal energy radiated per secondQ1:Q2=16:81