Question

An electron moves on a straight line path $XY$ as shown. The abcd is a coil adjacent to the path of electron. What will be the direction of current, if any, induced in the coil?

• A. The current will reverse its direction as the electron goes past the coil
• B. No current induced
• C. abcd
• D. adcb

Answer 1

Answer: (A)

The current will reverse its direction as the electron goes past the coil

Answer 2

When the electron moves from X to X, the flux linked with the coil abed (which is into the page) will first increase and then decrease as the electron passes by. So the induced current in the coil will be first anticlockwise and will reverse its direction (z.e. will become clockwise) as the electron goes past the coil.