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Concepts Of Physics MCQ Edition [Volume 2]PhysicsHeat Transfer

A hot body placed in a surrounding of temperature ₀ conforms to Newton's law of cooling, d dt = -k( - ₀) . At t = 0 , its temperature is ₁ . The mass of the body is m and its specific heat capacity is s . Determine the maximum heat that the body can lose.

Options

  1. Ams ₁
  2. Bms( ₁ + ₀)
  3. Cms( ₁ - ₀)
  4. Dms( ₁ - ₀) k

Correct answer

C. ms( ₁ - ₀)

Step-by-step solution

The body cools down according to Newton's law of cooling and its temperature decreases until it reaches thermal equilibrium with the surroundings. The minimum temperature the body can attain is the temperature of the surroundings, which is ₀ . The initial temperature of the body is ₁ . The maximum fall in temperature of the body is = ₁ - ₀ . The maximum heat lost by the body is given by Q = ms . Substituting the value of , we get Q = ms( ₁ - ₀) .

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