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GATE2015-2-39

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The total emissive power of a surface is $500 \: W/ m^2$ at a temperature $T_1$ and $1200 \: W/m^2$ at a temperature $T_2$, where the temperatures are in Kelvin. Assuming the emissivity of the surface to be constant, the ratio of the temperatures $\dfrac{T_1}{T_2}$ is

  1. $0.308$
  2. $0.416$
  3. $0.803$
  4. $0.874$
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