2. Solved Papers
  3. JCECE Engineering

JCECE Engineering JCECE Engineering Solved Paper-2005

  • question_answer
    An air bubble is released from the bottom of a pond and is found to expand to thrice its original volume as it reached the surface. If the atmospheric pressure is \[100\,\,kPa\], the absolute pressure at the bottom of lake in \[kPa\] is ... (assume no temperature variation) :

    A) \[33.3\]                               

    B) \[50.0\]

    C) \[100.0\]                             

    D) \[300.0\]

    Correct Answer: D

    Solution :

    Key Idea: In an isothermal change temperature remains constant. For isothermal change                 \[PV=RT=\]constant where, \[P=h\rho g=\]height\[\times \]density\[\times \]gravity \[\therefore \]  \[{{P}_{1}}{{V}_{1}}={{P}_{2}}{{V}_{2}}\] Given,\[{{V}_{2}}=3{{V}_{1}},\,\,{{P}_{2}}=1000\,\,kPa=100\times {{10}^{3}}Pa\] \[\therefore \]\[{{P}_{1}}=\frac{{{P}_{2}}{{V}_{2}}}{{{V}_{1}}}=\frac{100\times {{10}^{3}}\times 3{{V}_{1}}}{{{V}_{1}}}=300\,\,kPa\]


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