A solid sphere of radius `R` has a spherical cavity of radius `r` as shown in the figure. If the volume charge density `sigma` is uniformly distributed over the whole volume of the sphere, then electric field strength at the centre of the sphere will be

A sphere of radius 2R and mas M has a spherical cavity of radius R as shown in the figure. Find the value of gravitational field at a point P at a distance of 6R from centre of the sphere.

A sphere of radius 2R and mas M has a spherical cavity of radius R as shown in the figure. Find the value of gravitational field at a point P at a distance of 6R from centre of the sphere.

A charge Q coulomb is uniformly distributed over a sphere volume of radius R metres. What will be the expression for the energy of the system.

If the potential at the centre of a uniformly charged hollow sphere of radius R is V, then electric field at a distance r from the centre of sphere will be (rgtR) .

A non-conducting sphere of radius R has a spherical cavity of radius R//2 as shown. The solid part of the sphere has a uniform volume charge density rho . Find the magnitude and direction of electric field at point (a) O and (b) A.

A non-conducting sphere of radius R has a spherical cavity of radius R//2 as shown. The solid part of the sphere has a uniform volume charge density rho . Find the magnitude and direction of electric field at point (a) O and (b) A.

A charge Q coulomb is uniformly distributed over a sphere volume of radius R metres. Obtain an expression for the energy of the system.

An infinity long cylinder of radius R has an infinitely long cylindrical cavity of radius (R)/(2) are shown in the figure. The remaining portion has uniform volume charge density rho . The magnitude of electrical field at the centre of the cavity is-

An infinity long cylinder of radius R has an infinitely long cylindrical cavity of radius (R)/(2) are shown in the figure. The remaining portion has uniform volume charge density rho . The magnitude of electrical field at the centre of the cavity is-

An isolated non-conducting solid sphere of radius R is given an electric charge. The charge is uniformly distributed in the volume of sphere. The graph which shows the correct variation of magnitude of electric field with distance from the centre of the sphere is