A point charge `q` is located at the centre fo a thin ring of radius `R` with uniformly distributed charge `-q`, find the magnitude of the electric field strength vectro at the point lying on the axis of the ring at a distance `x` from its centre, if `x gt gt R`.

A thin half ring of radius R = 20 cm is uniformly charged with a total charge q = 0.70 nC .Find the magnitude of the electric field strength at the curvaite centre of this half-ring.

Point charge q and -q are located at the vertices of a square with diagonals 2l as shown in Fig. Find the magnitude of the electric field strength at a point located symmetrically with respect to the vertices of the square at a distnace x from its centre.

A ring of radius a contains a charge q distributed. uniformly ober its length. Find the electric field at a point. on the axis of the ring at a distance x from the centre.

A ring of radius R is with a uniformly distributed charge Q on it .A charge q is now placed in the centre of the ring .Find the increment in tension in the ring.

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

A thin nonconducting ring of radius R has a linear charge density lambda = lambda_(0) cos varphi , where lambda_(0) is a constant , phi is the azimutahl angle. Find the magnitude of the electric field strength (a) at the centre of the ring , (b) on the axis of the ring as a function of the distance x from its centre. Investegation the obtained function at x gt gt R .

A ring of radius R with a uniformly distributed charge q as shown in figure. A charge q_(0) , is now placed at the centre of the ring. Find the increment in-the tension in ring.

A ring of radius R has charge -Q distributed uniformly over it. Calculate the charge that should be placed at the center of the ring such that the electric field becomes zero at apoint on the axis of the ring at distant R from the center of the ring.

A non conduction ring of raducs R Has uniformly distributed positive charge Q.A small part of the ring of length d, is removed (d lt lt R) . The electric field at the centre of the ring now be .