Question

The heat radiated per unit area in 1 hour by a furnace whose temperature is 3000 K is (δ = 5.7 × 10^–8 W m^–2 K^–4)

(a) 1.7 × 10¹⁰ J

b) 1.1 × 10¹² J

(c) 2.8 × 10⁸ J

(d) 4.6 × 10⁶ J

Answer 1

Correct option: (a) 1.7 × 10¹⁰ J

Explanation:

According to Stefan’s law E = δ  T⁴

Heat radiated per unit area in 1 hour (3600s) is

= 5.7× 10^–8 × (300)⁴ × 3600 = 1.7 × 10¹⁰ J