Question

A transformer has 100 turns in its primary coil and 200 turns in its secondary coil. If the primary coil is supplied with 1.20 A and 270 V, what is the power output of the secondary coil?

Answer 1

The transformer formula may be written as follows:

`(I_1)/(I_2)=(V_2)/(V_1)=(N_2)/(N_1)`

where:

`\begin{gathered} I_1\text{ = current in primary coil} \\ I_2=\text{ current in secondary coil} \\ V_1=\text{ tension in primary coil} \\ V_2=\text{ tension in secondary coil} \\ N_1=\text{ number of turns in primary coil} \\ N_2=\text{ number of turns in secondary coil} \end{gathered}`

We have to find V2 and I2. So:

`\begin{gathered} (V_2)/(V_1)=(N_2)/(N_1) \\ (V_2)/(270)=(200)/(100) \\ V_2=540V \end{gathered}`

Also:

`\begin{gathered} (V_2)/(V_1)=(I_1)/(I_2) \\ (540)/(270)=(1.20)/(I_2) \\ I_2=0.60A \end{gathered}`

Then power output of the secondary coil is:

`\begin{gathered} P_2=V_2\cdot I_2_{} \\ P_2=540\cdot(0.60) \\ P_2=324W \end{gathered}`

Power output of the secondary coil equals 324 W.