Question

A small hole is made in a metallic hollow enclosure whose walls are maintained at a temperature of `10^(3)`K. then the amount of radiant energy emitted per metre square per second from the hole is
A. 56.7 J
B. 56.7 KJ
C. `10^(3)J`
D. data is in sufficient

Answer 1

Correct Answer - B
`E=sigmaT^(4)`
`=5.67xx10^(-8)xx(10^(3))^(4)`
`=5.67xx10^(-8)xx10^(12)=5.67xx10^(4)`
`=56.7xx10^(3)J`
`=56.7kJ`.