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, 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

Four identical charges each .q. are placed at four corners of a square of side .a.. Find the charge to be placed at the centre of the square so that the system of charges is in equilibrium

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 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 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 of a square and a charge q is at its centre. If the system is in equilibrium the value of q is

Four identical charges i.e. q is placed at the corners of a square of side a . The charge Q that must be placed at the centre of the square such that the whole system of charges in equilibrium is