2. Solved Papers
  3. CMC Medical

CMC Medical CMC-Medical VELLORE Solved Paper-2010

  • question_answer
    A body cools in 7 min from \[60{}^\circ C\] to \[40{}^\circ C.\] What time (in min) does it take to cool from \[40{}^\circ C\] to \[28{}^\circ C,\] if surrounding temperature\[10{}^\circ C\]? (Assume Newtons law of cooling)

    A)  3.5                                        

    B)  14

    C)  7                                            

    D)  10

    E)  None of these

    Correct Answer: C

    Solution :

                    From Newtons law of cooling, \[\frac{{{\theta }_{1}}-{{\theta }_{2}}}{t}=\left( \frac{{{\theta }_{1}}+{{\theta }_{2}}}{2}-{{\theta }_{0}} \right)\] Therefore, \[\frac{60{}^\circ -40{}^\circ }{7}\propto \left( \frac{60{}^\circ +40{}^\circ }{2}-10{}^\circ  \right)\]             ?(i) \[\frac{60{}^\circ -40{}^\circ }{t}\propto \left( \frac{40{}^\circ +28{}^\circ }{2}-10{}^\circ  \right)\]              ?(ii) \[\therefore \]  \[t=7\,s\]


You need to login to perform this action.
You will be redirected in 3 sec spinner