A spherical body of 5 cm radius is maintained at a temperature of `327^(@)C`. The wavelength at which maximum energy radiated will be nearly `(b=2.898xx10^(-3)m" "K)`

Options

A. 1.72W
B. 2.73W
C. 11.0W
D. 2.15W

Answer

C

Explanation

The surface area of the ball is `A= 4pi r^(2) = (4pi) (0.02m)^(2) = 0.005 m^(2)`
and its absolute temperature is `T= 327 + 273 = 600K`
Hence the rate of the energy radiated by it is
`E= e sigma AT^(4) = 0.3 xx 5.67 xx 10^(-8) xx 0.005 xx (600)^(4)= 11.0W`