A student cycles 2 km North, then turns West and cycles 2.5 km, then turns South and cycles 2 km, then turns to his left and cycles 4.5 km. Where is he now with respect to the starting position?
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