BVP Medical BVP Medical Solved Paper-2003

  • question_answer
    An electron having charge \[1.6\times {{10}^{-19}}C\]and mass \[9\times {{10}^{-31}}\] kg is moving with\[4\times {{10}^{6}}\]m/s speed in a magnetic field of \[2\times {{10}^{-1}}\]tesla in a circular orbit. The force acting on an electron and the radius of circular orbit will be:

    A) \[1.28\times {{10}^{14}}N,1.1\times {{10}^{-3}}m\]

    B) \[1.28\times {{10}^{15}}N,1.2\times {{10}^{-12}}m\]

    C)  \[1.28\times {{10}^{-13}}N,1.1\times {{10}^{-4}}m\]      

    D)  none of these

    Correct Answer: C

    Solution :

                    Force produced on an electron is given by \[F=e\upsilon B=1.6\times {{10}^{-19}}\times 4\times {{10}^{6}}\times 2\times {{10}^{-1}}\] \[=1.28\times {{10}^{-13}}N\] Since electron is moving in circular orbit So,        \[\frac{m{{\upsilon }^{2}}}{r}=e\upsilon B\] or            \[r=\frac{m\upsilon }{eB}=\frac{9\times {{10}^{-31}}\times 4\times {{10}^{6}}}{1.6\times {{10}^{-19}}\times 2\times {{10}^{-1}}}\] \[=1.1\times {{10}^{-4}}m\]


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