Answer:
Explanation:
Stefan's Boltzman Law gives the value of radiation from a black body at a particular temperature. The relation is
E = eσ ( T₂⁴ -T₁⁴ )
e is emmisivity , σ is a constant = 5.67 x 10⁻⁸ , E is energy emitted per unit time per unit area
E = .915 x 5.67 x 10⁻⁸ x ( 303⁴ -293⁴ )
= .915 x 5.67 x 10⁻⁸ x ( 84.28 -73.70 ) x 10⁸
= 55 W / m²s
Area A = 1.45 m²
time t = 14.3 min
= 858 s
Total radiation
= 55 x 858 x 1.45 W
= 68425 J
