BCECE Medical BCECE Medical Solved Papers-2011

  • question_answer
    A current of 0.01 mA passes through the potentiometer wire of a resistivity of \[{{10}^{9}}\Omega \] cm and area of cross-section \[{{10}^{-2}}\,c{{m}^{2}}\]. The potential gradient is

    A)  \[{{10}^{9}}V/m\]

    B)  \[{{10}^{11}}V/m\]

    C)  \[{{10}^{10}}V/m\]

    D)  \[{{10}^{8}}V/m\]

    Correct Answer: D

    Solution :

    Potential gradient is                 \[k=\frac{V}{l}=\frac{iR}{l}\] \[(\therefore \,V=iR)\]                 \[=\frac{i\times \rho \frac{l}{A}}{l}\] \[\left( \because R=\rho \frac{l}{A} \right)\]                 \[=\frac{i\rho }{A}\] \[\therefore \] \[k=\frac{0.01\times {{10}^{-3}}\times {{10}^{9}}\times {{10}^{-2}}}{{{10}^{-2}}\times {{10}^{-4}}}={{10}^{8}}V/m\]


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