Question

The temperature of a black body corresponding to which it will emit energy at the rate of $1watt/c{m}^2$ will be

• A. 650K
• B. 450K
• C. 350K
• D. 250K

Answer 1

The correct option is A 650K

$E\propto T^4⟹E=\sigma T^4$
$\sigma =5.67\ast {10}^{8}W{m}^2{k}^4$
$1\ast {10}^{-4}=5.67\ast {10}^8\ast T^4$
$T=648k\cong 650k$