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Concepts Of Physics MCQ Edition [Volume 2]PhysicsHeat Transfer

Newton's law of cooling represents a special case of

Options

  1. APlanck's law
  2. BKirchhoff's law
  3. CStefan's law
  4. DWien's displacement law

Correct answer

C. Stefan's law

Step-by-step solution

According to Stefan's law, the net rate of heat loss by radiation from a body at temperature T in surroundings at temperature T₀ is given by P = e A (T^4 - T₀^4) . Let T = T₀ + T , where the temperature difference T is very small compared to T₀ . Substituting this into Stefan's law: P = e A [(T₀ + T)^4 - T₀^4] P = e A T₀^4 [ (1 + T T₀ )^4 - 1 ] Using the binomial expansion for small T T₀ and neglecting higher-order terms: P e A T₀^4 [1 + 4 T T₀ - 1 ] P 4 e A T₀^3 T Since 4 e A T₀^3 is a constant for a given body an

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