Four charges equal to `-Q` are placed at the four corners of a square and a charge q is at its centre. If the system is in equilibrium the value of q is

Four charges equal to -Q are placed at the four corners fo a square and a charge q is at its centre, If the system is in equilibrium the value of q si

Four charges each equal to -Q are placed at the four corners of a square and a charge q is at its center. If the system is in equilibrium, the value of q is :

Four charges equal to - Q placed at the four corners of a sqare and a charge q is its centre. If the system is in equilibrium, the value of q is

Four charges +Q, -Q, +Q, -Q are placed at the corners of a square taken in order. At the centre of the square

Four charges each of -Q , are placed at the four corners of a square. Find out the value of a charge q placed at the centre of the square, such that all the charges would be at equilibrium.

Four charges Q-Q, Q-Q are placed at the corners of a square as shown . The potential is zero at points

Four charges, each of value q, are placed at the four corners of a square of side a. What is the potential at the centre of the square