Two charges +q each are kept at two of the vertices of equilateral triangle. The resultant electric

Question

Two charges +q each are kept at two of the vertices of equilateral triangle. The resultant electric field at the center is E. One more charge --q is placed at the 3rd vertex. The resultant field at the center will be

Professor PC Thomas Classes · Answer

The field due to each +q charge at the center is the same in magnitude, with components that combine to give resultant E. Adding a -q charge at the third vertex creates a field also equal in magnitude but in the opposite direction of the resultant of the first two. The total field is 2E.