Two objects have exactly the same shape. Object A has emissivity of 0.3 and object B has emissivity of 0.6. If each radiates the same power, then

Options

A. temperature of A is twice that of B measured in K
B. temperature of B is twice that of A in `.^(@)k`
C. temperature of A is `2^(1//4)` times that of B in `.^(@)k`
D. temperature of B is 2 times that of A in `.^(@)C`

Answer

C

Explanation

`P_(1)= sigma A rho_(1) T_(1)^(4) and P_(2)=sigma A rho_(2)T_(2)^(4)`
`P_(1)=P_(2)`
`rho_(1)T_(1)^(4)=rho_(2)T_(2)^(4)`
`((T_(1))/(T_(2)))=(rho_(1))/(rho_(2))=(0.6)/(0.3)=2`
`T_(1)=2^(1//4)T_(2)`