The power radiated by a black body (emissivity=1)of surface area 0.5 m² is at a temperature of 40 $\circ$ C,while its surroundings are at a temperature of 20 $\circ$ C.What is the net power radiated by this object? (The Stefan-Boltzmann constant has a value of 5.67 * 10^-8 W/m² K⁴).

Question

Quizplus · Accepted Answer

The net power radiated by a black body is given by the Stefan-Boltzmann law: P = σA(T₁⁴ - T₂⁴), where σ is the Stefan-Boltzmann constant, A is the surface area, T₁ is the temperature of the body, and T₂ is the temperature of the surroundings. Converting temperatures to Kelvin: T₁ = 313 K, T₂ = 293 K. Plugging in the values: P = 5.67 * 10⁻⁸ * 0.5 * (313⁴ - 293⁴) = 63.2 W.

The Power Radiated by a Black Body (Emissivity=1)of Surface Area ∘\circ∘

The Power Radiated by a Black Body (Emissivity=1)of Surface Area $\circ$