A charge +Q is uniformly distributed over a thin ring of the radius R. The velocity of an electron at the moment when it passes through the centre O of the ring, if the electron was initially at far away on the axis of the ring is (m=mass of electron, `K=1/(4pi epsi_(0))`)

Charge q is uniformly distributed over a thin half ring of radius R . The electric field at the centre of the ring is

A charge +Q is uniformly distributed over a thin ring of a radius R. Find the velocity of a negative point charge -Q at the moment it passes through the centre of the ring if it was initially at rest at infinity on the axis of the ring. The mass of the charge-Q is equal to m.

Charges q is uniformly distributed over a thin half ring of radius R . The electric field at the centre of the ring is

Charges q is uniformly distributed over a thin half ring of radius R . The electric field at the centre of the ring is

A charge q is uniformly distributed over a quarter circular ring of radius r . The magnitude of electric field strength at the centre of the ring will be

Electric charge Q is uniformly distributed around a thin ring of radius a. find the potential a point P on the axis of the ring at a distance x from the centre of the ring .