Question

NTSE physics question The force of repulsion between two parallel wires is ‘f’ when each one of them carries a certain current ‘ I ‘. If the current in each is doubled, the force between them would be (a) 2f (b) 3f (c) 4f (d) f / 4 Please explain! Thanks

Answer 1

Force f of repulsion between two wires is proportional to the current i1 and  i2 (in either wire).

so if both currents are doubled, then the force is 4 times f.