Question

A transformer with 660 turns in its primary coil has to decrease the voltage from 4840 V to 220 V for home use. How many turns should there be on the secondary coil? ______:turns

Answer 1

Given:

The primary coil of the transformer has 660 turns. Thus, Np = 600.

The primary voltage of the transformer is: Vp = 4840 v

The secondary voltage of the transformer is: Vs = 220 v

To find:

The number of turns of the secondary coil (Ns).

Step-by-step explanation:

The primary voltage Vp, secondary voltage Vs, a number of turns on primary coil Np and on secondary coil Ns are related as:

`(V_p)/(V_s)=(N_p)/(N_s)`

Rearranging the above equation, we get:

`N_s=N_p(V_s)/(V_p)`

Substituting the values in the above equation, we get:

`\begin{gathered} N_s=660*\frac{220\text{ v}}{4840\text{ v}} \\ \\ N_s=(145200)/(4840) \\ \\ N_s=30 \end{gathered}`

Final answer:

The number of turns on the secondary coil of the given step-down transformer is 30.