If the sun’s surface radiates heat at $6.3 \times {10^7}W{m^{ - 2}}$. Calculate the temperature of the sun assuming it to be a black body $(\sigma = 5.7 \times {10^{ - 8}}W{m^{ - 2}}{K^{ - 4}})$
Medium
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(a)From Stefan’s law $E = \sigma {T^4}$
${T^4} = \frac{E}{\sigma } = \frac{{6.3 \times {{10}^7}}}{{5.7 \times {{10}^8}}} = 1.105 \times {10^{15}} = 0.1105 \times {10^{16}}$
$T = 0.58 \times {10^4}K = 5.8 \times {10^3}K$
${T^4} = \frac{E}{\sigma } = \frac{{6.3 \times {{10}^7}}}{{5.7 \times {{10}^8}}} = 1.105 \times {10^{15}} = 0.1105 \times {10^{16}}$
$T = 0.58 \times {10^4}K = 5.8 \times {10^3}K$
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