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

No. of turns in secondary coil are 5.

Transformer Type: STEP DOWN TRANSFORMER

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.