Two long conductors, separated by a distance r carry current I1 and I2 in the same direction. They exert a force F on each other. Now, the current in one them is increased to 3 times and the direction is reversed. The distance is also increased to 5r. What is the new value of the force between them?

MCQs on magnetic force, magnetic field motion, electric and magnetic field motion, biot savart law, amperes circuital law, solenoid and toroid, two parallel currents forces, moving coil galvanometer, current loop and magnetic dipole torque.