A) e = 0.18
B) e = 0.02
C) e = 0.2
D) e = 0.15
Correct Answer: A
Solution :
\[Q=E\,\,\,\,At\,=e\sigma ({{T}^{4}}-T_{0}^{4})At\] where, t is time \[{{T}_{0}}\]= temperature of surrounding When, \[T>{{T}_{0}}\] \[Q=e\sigma {{T}^{4}}\,\,At\] \[300=e\times (5.67\times {{10}^{-8}}){{(1000)}^{4}}\] \[(5.00\times {{10}^{-4}})(60)\] or \[e=0.18\]You need to login to perform this action.
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