JEE Main & Advanced Sample Paper JEE Main Sample Paper-43

  • question_answer
    Two concentric spheres of radii R and r have similar charges with same surface charge densities\[(\sigma )\]. What is the electric potential at their common centre?

    A)  \[\frac{\sigma }{{{\varepsilon }_{0}}}\]                             

    B)  \[\frac{\sigma }{{{\varepsilon }_{0}}}\,(R-r)\]

    C)  \[\frac{\sigma }{{{\varepsilon }_{0}}}\,(R+r)\]                  

    D)  None of these

    Correct Answer: C

    Solution :

     Let Q and q be the charges on the spheres. The potential at the common centre will be \[=0\] \[\therefore \,\,|\xi |\,=\,\left| \frac{-\Delta \phi }{\Delta t} \right|=\,\left| -\left( \frac{0-BA}{\frac{T}{4}-0} \right) \right|=\frac{4BA}{T}\] But       \[(\Delta \phi ={{\phi }_{2}}-{{\phi }_{1}})\] \[T=\frac{2\pi }{\omega }\]    \[\Rightarrow \]

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