Four point charges qA = 2 µC, qB = –5 µC, qC = 2 µC, and qD = –5 µ C are located at the corners of a square ABCD of side 10 cm. What is the force on a charge of 1 µC placed at the centre of the square?

Four point charges q_A= +5 muC, q_B = -5 muC, q_C = +5 muC, and q_D=-5muC are located at the corners of a square ABCD of side 10 cm. What is the force on a charge of 1 muC placed at the centre of the square?

Three point electric charges q_1 = 6µC, q_2 = 4µC and q_3 = -8µC are placed on the circumference of a circle of radius 1m as shown in the figure. What is the value of the charge q, placed on the circle if the potential at the centre of the circle is zero?