Question

The primary 40-turn coil of an ideal transformer is supplied with 120 V (rms). If the rms voltage output of the secondary coil is 15 V, how many turns are in the secondary coil, and what type of transformer is this

Answer 1

No. of turns in secondary coil are 5.

Transformer Type: STEP DOWN TRANSFORMER

Step-by-step explanation:

The relationship of the no. of turns in transformer secondary and primary coils with their voltages is known as the turn ration. The formula for turns ratio is as follows:

Np/Ns = Vp/Vs

where,

Np = No. of turns in primary coil = 40

Ns = No. of turns in secondary coil = ?

Vp = Voltage supplied to primary coil = 120 V

Vs = Voltage output of secondary coil = 15 V

Therefore,

40/Ns = 120 V/15 V

Ns = 40/8

Ns = 5

TYPE OF TRANSFORMER:

Since, this transformer decreases the voltage value at the output. Hence it is a STEP DOWN TRANSFORMER.