Four identical charges Q are fixed at the four corners of a square of side a. The electric field at a point P located symmetrically at a distance `a//sqrt(2)` from the center of the square is

Four identical point charges q are placed at four corners of a square of side a. Find the potential energy of the charge system. .

Four identical point charges q are placed at four corners of a square of side a. Find the potential energy of the charge system. .

Four point charges are placed at the corners of a square of side l. Calculate potential at the centre of square.

Four point charges are placed at the corners of a square of side l. Calculate potential at the centre of square.

Four identical positive point charges Q are fixed at the four corners of a square of side length l . Another charged particle of mass m and charge +q is projected towards centre of square from a large distance along the line perpendicular to plane of square. The minimum value of initial velocity v_(0) (in m/s) required to cross the square is ? (m = 1 gm, l = 4 sqrt(2) m, Q =1 mu c, q = 0.5 muc)