Answer to Question #348227 in Physics for Aya

Question

Upon the heating of black body the maximum of its spectrum shiftedfrom 690 nm to 500 nm. By what factor did the radiant emittance increase?

Answer 1

$\lambda_{\max}=\frac{b}{T},\quad u=\sigma T^4$

$\frac{u_2}{u_1}=\frac{T_2^4}{T_1^4}=\frac{\lambda_{\max 1}^4}{\lambda_{\max 2}^4}=\frac{690^4}{500^4}=3.6$