2. Sample Papers
  3. NEET

NEET Sample Paper NEET Sample Test Paper-60

  • question_answer
    A rectangular film of liquid is extended from \[(4cm\times 2cm)\]to\[(5cm\times 4cm)\]If the work done is \[3\times {{10}^{-4}}J,\]the value of the surface tension of the liquid is:

    A) 8N/m                           

    B) 0.250N/m

    C) 0.125N/m         

    D) 0.2N/m

    Correct Answer: C

    Solution :

    [c] \[{{A}_{1}}=8\times {{10}^{-4}}{{m}^{2}}{{A}_{2}}=20\times {{10}^{-4}}{{m}^{2}}\] \[W=3\times {{10}^{-4}}J\,\] \[W=2T\Delta A\]           [?2? thin film has two surfaces] \[3\times {{10}^{-4}}=2.T.\,[20\times {{10}^{-4}}\,-8\times {{10}^{-4}}]\] \[3\times {{10}^{-4}}\,24T\times {{10}^{-4}}\] \[T=0.125N/m\]


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