A radiator in a domestic heating system operates at a surface temperature of 55°C. Assuming the radiator behaves as a black body, the rate at which it emits the radiant heat per unit area is (assume σ = 5.67 × 10-8 W/(m2K4))?

0.66 kW/m²
0.0005 kW/m²
0.5 kW/m²
66 kW/m²

LohaHridoy

4 views

2025-01-04 04:42

1 Answers

AhmedNazir

Option 1 : 0.66 kW/m2

Concept:

The radiant heat transfer is given as Q = σAT⁴

where, σ = Stefan-Boltzmann constant. (5.67 × 10^-8 W/m²/K⁴), A = area of body, T = absolute temperature

Calculation:

Given:

T = 55°C = 55 + 273 = 328 K, A = 1 m²

⇒ 5.67 × 10^-8 × (328)⁴

= 656.26 W/m²

= 0.656 kW/m²

4 views Answered 2022-09-04 04:29

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