Question

The primary coil of a transformer has $1,32,000$ turns and is connected to A.C. input source of $220\text{V}$. The secondary coil has $2,400$ turns. Find the output voltage.

• A. 4.0 V
• B. 4.5 V
• C. 6.0 V
• D. 5.5 V

Answer 1

The correct option is A 4.0 V

Given,
No. of turns in the primary coil, ${\text{N}}_{\text{p}}=1,32,000$
No. of turns in the secondary coil, ${\text{N}}_{\text{s}}=2,400$
Voltage across the primary coil, ${\text{E}}_{\text{p}}=220\text{V}$
Let the voltage across the secondary coil be ${\text{E}}_{\text{s}}$.
We know, $\frac{{\text{E}}_{\text{s}}}{{\text{E}}_{\text{p}}}=\frac{{\text{N}}_{\text{s}}}{{\text{N}}_{\text{p}}}$

${\text{E}}_{\text{s}}=\frac{{\text{N}}_{\text{s}}}{{\text{N}}_{\text{p}}}\times {\text{E}}_{\text{p}}$

$\Rightarrow \frac{2,400}{1,32,000}\times 220$

$=\frac{5,28,000}{1,32,000}=4.0\text{V}$