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Concepts Of Physics MCQ Edition [Volume 2]PhysicsHeat Transfer

Two bodies, A and B , which possess equal surface areas, are maintained at temperatures of 10^ C and 20^ C . The ratio of the thermal radiation emitted by A and B in a specific time interval is

Options

  1. A1 : 2
  2. B1 : 4
  3. C1 : 1.15
  4. D1 : 16

Correct answer

C. 1 : 1.15

Step-by-step solution

According to Stefan-Boltzmann law, the thermal radiation emitted by a body per unit time is given by E = A T^4 Given temperatures are T_A = 10^ C = 283 K and T_B = 20^ C = 293 K The ratio of thermal radiation emitted is E_A E_B = ( T_A T_B )^4 = ( 283 293 )^4 E_B E_A = ( 293 283 )^4 = (1 + 10 283 )^4 Calculating the value, we get ( 293 283 )^4 1.149 1.15 Therefore, the ratio is 1 : 1.15

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