Question

The temperature of a perfect black body is 727∘C and its area is 0.1m2. If Stefan's constant is 5.67×10−8W/m2K4, then heat radiated by it in 1 minutes is :​

Answer 1

Explanation:

Given The temperature of a perfect black body is 727∘C and its area is 0.1 m2. If Stefan's constant is 5.67×10−8 W/m2K4, then heat radiated by it in 1 minutes is  

• According to Stephan’s Boltzman law, the rate of heat flow through the body is given by
• dQ / dt = σ A T^4
•             = 5.67 x 10^-8 x 0.1 x (727 + 273)^4  
•            = 5.67 x 10^-8 x 0.1 x (10^3)^4
•            = 0.567 x 10^4
•            = 5670 W
• Now heat radiated in 1 minute is  
• Q = 5670 x 1 x 60

Q = 340200 J