VMMC VMMC Medical Solved Paper-2003

  • question_answer
    A proton and an \[\alpha \]-particle follow the same circular path in a transverse magnetic field. Their kinetic energies are in the ratio:

    A)  1 : 4      

    B)                         4 : 1                      

    C)  1 : 2                      

    D)         1 : 1

    Correct Answer: D

    Solution :

    Radius of circular path in a transverse magnetic field is given by \[r=\frac{m\upsilon }{Bq}\] \[=\frac{\sqrt{2mE}}{Bq}\]                 or            \[\frac{mE}{{{q}^{2}}}=\text{cosntant}\] [\[\because \] B and r are constant for proton and\[\alpha \]particle] \[\therefore \]  \[\frac{{{E}_{_{1}}}}{{{E}_{2}}}=\frac{{{q}_{1}}^{2}}{{{q}_{2}}^{2}}.\frac{{{m}_{2}}}{{{m}_{1}}}\] For proton, \[{{q}_{1}}=e,\,{{m}_{1}}=m\] For \[\alpha -\]particle; \[{{q}_{2}}=2E,\,{{m}_{2}}=4m\] Hence,                  \[\frac{{{E}_{1}}}{{{E}_{2}}}=\frac{{{e}^{2}}}{4{{e}^{2}}}.\frac{4m}{m}\]                                 \[=\frac{1}{1}=1:1\]


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