Question

A circular coil with a radius of 0.4 meters wrapped 47 times is spun at a frequency of 21 Hz in a uniform magnetic field to form a generator. It is then connected to the primary transformer. The primary side has 36 turns and the secondary side has 15 turns. The maximum secondary current is 6 amps and the resistance of the coil on the primary side is 3 Ohms. What is the amount of the magnetic field in the generator in milli-Tesla?

Answer 1

Parameters of the circular coil:

Radius R = 0.4 m

Area, A =

Number of turns, N = 47.

Frequency of rotation, f = 21 Hz

Angular frequency,

Let the magnetic flux density through the coil be B.

According to Faraday's law the voltage induced in the coil = (Ignorning the sign due to Lenz's law as is not relevant in the problem)

where, is the magnetic flux linked with the coil and

So,

This coil is connected to the primary transformer:

Primary voltage =

Transformer parameters:

Number of turns in the primary side,

Number of turns in the secondary side,

Resistance on the primary side,

Primary current,

Secondary current,

From transformer relation:

The amount of magnetic field in the generator is 2.42 mT.

Regards