A, B, C, D and E are standing in a line facing North. E is standing 40 metres left to B. A is standing 20 metres left to C. D is standing 20 metres right to E and 50 metres right to C. Where is B standing from D?
Two particles with charges q1 and q2 are kept at a certain distance to exert force F on each other. If the distance is reduced to one-fifth, then the force between them is