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Concepts Of Physics MCQ Edition [Volume 2]PhysicsHeat Transfer

A hot liquid is placed in a large room. The temperature of the liquid is plotted as a function of time. Which of the curves shown could represent the plot?

Options

  1. Aa
  2. Bd
  3. Cc
  4. Db

Correct answer

A. a

Step-by-step solution

According to Newton's law of cooling, the rate of loss of heat is directly proportional to the difference in temperature between the body and its surroundings. d dt = -k( - ₀) where is the temperature of the liquid at time t , ₀ is the temperature of the surroundings, and k is a positive constant. Integrating the above equation, we get: = ₀ + ( _i - ₀)e^ -kt where _i is the initial temperature of the liquid. This equation represents an exponentially decaying curve. The temperature decreases continuously and approac

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