A square loop of side is placed horizontally on a table so that side lies along the…
PHYSICS · Multi-part · CBSE · Physics · Magnetic Effects of Electric Current · Magnetic Effects of Electric Current
Problem
A square loop ABCD of side 6cm is placed horizontally on a table so that side AB lies along the north–south direction. A uniform magnetic field of 0.20T acts from east to west. A current of 3A is established in the loop in the clockwise sense as viewed from above.
(i) For each side AB, BC, CD and DA, state the direction of the force acting on that side (towards the centre, away from the centre, upward, or downward) and justify your answer.
(ii) Show that the net force on the loop is zero but that the four forces constitute a couple. Briefly describe the sense of rotation produced.
(iii) Explain how such a turning effect is utilised in the working of an electric motor.