Question

Four point charges qA = 2 µ C and qB = -5 µ C, qC=

2 µ c and qD = -5 µ c are located at the corners of a

square A B C D of side 10 cm. What is the force on a

charge of 2 µ c placed at the centre of the square?​

Answer 1

The charge placed at the vertex A is (+)2uC and also at vertex C is (+)2uC.

Since, both the charges are equal in magnitude and are placed diagonally opposite to each other, their resultant at point E will turn out zero. That is the vectorial summation of forces F(a) and F(c) will be zero at E.

Similarly, the vectorial summation of forces F(d) and F(b) will be zero at the point E.

Hence, the net force acting at point E will be the summation of forces acting along the diagonals AC and DB. But the forces acting along these diagonals is zero.

Therefore, the net force acting on the 2uC charge placed at the centre is zero(0).

Thus, the answer is Zero(0)-newton.