Short Q/A Electromagnetism

What is the direction of rotation of the coil (shown in the figure) when the switch is closed? Label the diagram with the direction of forces forming a couple and the rotation of the coil.

When the switch is closed, current starts flowing in the coil. By applying Fleming’s Left-Hand Rule, the force on one side of the coil moves up, while the force on the opposite side moves down. This creates a couple (a pair of equal and opposite forces) that causes the coil to rotate. The direction of … Read more

Bar magnets are dropped in long pipes made up of plastic and copper (of the same length) simultaneously. The bar magnet comes out later through the copper pipe than through the plastic pipe. Why?

When the bar magnet moves through the copper pipe, it induces eddy currents in the pipe due to Faraday’s Law of Electromagnetic Induction. These eddy currents create a magnetic field that opposes the motion of the magnet, according to Lenz’s Law, causing the magnet to slow down. In contrast, the plastic pipe is a non-conductor … Read more

Two parallel straight conductors carrying current in the same direction attract each other? Explain why. What will you conclude if the direction of current in conductors is opposite?

When two parallel conductors carry current in the same direction, they produce magnetic fields around them. According to Ampere’s Right-Hand Rule, the magnetic field due to one conductor exerts a force on the other. By Laplace’s Force Law, the two conductors experience an attractive force because the magnetic field of one conductor exerts a force … Read more