Three charges -q, Q and -q are placed at equal distances on a striaght line. If the potential energy of the system of three charges is zero, then what is the ratio of Q:q?

Two point charges 4Q and Q are separated by a distance of 1 m in air. Also calculate the electrostatic potential energy of the system of two charges, taking Q = 2 xx 10^-7C .

Four point charges Q, q, Q and q are placed at the corners of a square of side 'a' as shown in the figure. Find the potential energy of this system?

Three point charges q, 2q and 8q are to be placed on a . 9cm long straight line. Find the . positions where the charges shouldbe placed such that the potential energy . of this sysrem is minimum. In this situation, what is the . electric field at the charge q due to the other two charges?

The point charges Q and -2Q are placed at some distance apart. If the electirc field at the location of Q is E, the electric field at the location of -2Q will be

Two poit charges of charge values Q and q are placed at a distance of x and x/2 respectively from a third charge of charge value 4q, all charges being in the same striahgt line. Calculate the magnitude and nature of charge Q, such that the net force experienced by the charge q is zero.

Two point charge +q and -q are separated by a distance d. Where besides at infinity is the electric potential zero?

Two point charges q_1 and q_2 are kept at a distance of r_(12) in air. Deduce the expression for the electrostatic potential energy of the system.

A point charge +q , is placed at a distance d from an isolated conducting plane. The field at a point P on the other side of the plane is

A charge q is placed at the centre of the line joining two exactly equal positive charges Q. the system of three charges will be in equilibrium, if q is equal to: