MCQ
Calculate radiation power for sphere whose temperature is $227^{\circ} C$ and radius $2\, m$ and emissivity $0.8$ (in $W$)
- ✓$1425$
- B$1500$
- C$1255$
- D$1275$
✓
Answer
Correct option: A.
$1425$
a
The expression of power is given as,
The expression of power is given as,
$P =\sigma AeT ^{4}$
Substitute the values.
$P =\left(5.67 \times 10^{-8}\right)\left(4 \pi \times 2^{2}\right)(0.8)(227+273)^{4}$
$\approx 1425 W$
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