Question 4: Thermodynamics & KTG

Question

Calculate radiation power for sphere whose temperature is 227$$^\circ$$C, radius 2 m and emissivity 0.8.

Accepted Answer

Temperature of sphere, $$T=227^{\circ} \mathrm{C}$$
$$=273+227=500 \mathrm{~K}$$
Radius, $$\quad r=2 \mathrm{~m}$$
Emissivity, $$e=0.8$$
$$	herefore$$ Radiation power of sphere $$=$$ Radiated energy per second
$$\begin{aligned}
& =\sigma A e T^4 \
& =5.67 	imes 10^{-8} 	imes 4 \pi 	imes 2^2 	imes 0.8 	imes(500)^4 \
& =142502.6 \mathrm{~W}=142.5 \mathrm{~kW}
\end{aligned}$$

Answer

142.5 kW

Answer

1500 W

Answer

1255 W

Answer

1575 W

Thermodynamics & KTG

Calculate radiation power for sphere whose temperature is 227$^\circ$C, radius 2 m and emissivity 0.8.

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