2. Solved Papers
  3. Manipal Medical

Manipal Medical Manipal Medical Solved Paper-2014

  • question_answer
    What is the potential energy of the soap film formed on a frame of area \[4\times {{10}^{-3}}{{m}^{2}}?\] If the area of the film is reduced by half, the change in its potential energy will be (surface tension of the soap solution is \[4\times {{10}^{-3}}\] H/m)

    A) \[32\times {{10}^{-5}}J,16\times {{10}^{-5}}J\]

    B) \[16\times {{10}^{-5}}J,8\times {{10}^{-5}}J\]

    C) \[48\times {{10}^{-5}}J,12\times {{10}^{-5}}J\]

    D) \[36\times {{10}^{-5}}J,2\times {{10}^{-5}}J\]

    Correct Answer: A

    Solution :

    Potential energy of the film  \[=2TA\] \[=2\times 40\times {{10}^{-3}}\times 4\times {{10}^{-3}}\]             \[=32\times {{10}^{-5}}J\] Change in potential energy                      \[=2T\Delta A\]                      \[=2\times 40\times {{10}^{-3}}[4\times {{10}^{-3}}-2\times {{10}^{-3}}]\]                      \[=16\times {{10}^{-5}}J\]


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