The earth receives its surface radiation from the sun at the rate of 1400 `W//m^(2)`. The distance of the centre of the sun from the surface of the earth is `1.5 xx 10^(11)` m and the radius of the sun is `7.0 xx 10^(8)` m. Treating sun as a black body, it follows from the above data that its surface temeperature is

Answer

`5803`

Explanation

Given
`((sigmaT^(4))(4piR^(2)))/((4pir^(2))) =1400`
`T = ((1400 xx r^(2))/(sigma R^(2)))^(1//4)`
`[(1400xx(1.5xx10^(11))^(2))/((5.67xx10^(-8))xx(7xx10^(8))^(2))]^(1//4) = 5803 K`