A thin circular ring of the area is held perpendicular to a uniform magnetic field of induction. A small cut is made in the ring and a galvanometer is connected across the ends such that the total resistance of the circuit is . When the ring is suddenly squeezed to zero areas, the charge flowing through the galvanometer is:
The explanation for the correct option:
Step 1: Given data
Step 2: Formula
Step 3: Calculation
The magnetic flux is given by the formula
The induced emf is given by:
is the change in magnetic flux.
is the change in time.
After the ring is suddenly squeezed to zero areas,
Induced emf is produced when the magnetic flux changes.
The current is given by
is the current.
is the emf.
Now substitute the value of current and induced emf in the above equation ( equating equation 1and 2)
Hence, Option(B) is correct.