Physics

Problem

Three-point charges of

+2 \mu\text{C}

-3 \mu\text{C}

and

-3 \mu\text{C}

are kept at the vertices

A

B

and

C

respectively of an equilateral triangle of side 20 cm as shown in the figure. What should be the sign and magnitude of the charge (

q

) to be placed at the mid-point (

M

) of side

BC

so that the charge at

A

remains in equilibrium?