Question

A conducting loop lies flat on a horizontal tabletop in a region where the magnetic field points straight down. The magnetic field disappears suddenly. When viewed from above, what is the direction of the induced current in this loop as the field disappears?

Answer 1

By applying Lenz's law and the right-hand rule, we determine that the induced current will flow in a counterclockwise direction when viewed from above as the downwards magnetic field disappears.

Step-by-step explanation:

When the magnetic field pointing straight down disappears suddenly, Lenz's law must be used to determine the direction of the induced current in the conducting loop. According to Lenz's law, the induced current will flow in a direction that creates a magnetic field to oppose the change in flux. Since the disappearing external field is downwards, the induced magnetic field must be upwards to oppose the reduction in flux. Applying the right-hand rule (RHR-2), we point the thumb upward to represent the induced field, and the fingers curl in the direction of the current. When viewed from above, as the field disappears, the fingers will curl in a counterclockwise direction, which is the direction of the induced current.