Measurements of the total emissive power of a near-black surface at three different…

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Problem

Measurements of the total emissive power

R

of a near-black surface at three different temperatures are given below. Temperature

T

(K): 700, 900, 1100 Measured

R

(

\text{W\,m}^{-2}

1.33\times10^{4}

3.74\times10^{4}

8.25\times10^{4}

Assuming the surface behaves as an ideal blackbody, which of the following values is the best estimate of the Stefan constant

\sigma

deduced from these readings? (a)

5.6\times10^{-5}\,\text{W\,m}^{-2}\,\text{K}^{-4}

(b)

5.6\times10^{-7}\,\text{W\,m}^{-2}\,\text{K}^{-4}

(c)

5.6\times10^{-8}\,\text{W\,m}^{-2}\,\text{K}^{-4}

(d)

5.6\times10^{-4}\,\text{W\,m}^{-2}\,\text{K}^{-4}