Question

In a transformer, the number of turns in the primary coil is $140$ and that in the secondary coil is $280$ . If the current in the primary coil is $4 \text{ A}$ , then that in the secondary coil is

• A. $4 \text{ A}$
• B. $2 \text{ A}$
• C. $6 \text{ A}$
• D. $10 \text{ A}$

Answer 1

Answer: (B)

$\textit{I}_{2} \textit{N}_{2} = \textit{I}_{1} \textit{N}_{1}$
$∴$ $\textit{I}_{2} = \frac{\textit{I}_{1} \textit{N}_{1}}{\textit{N}_{2}} = \frac{4 \times \text{140}}{\text{280}} = 2 \text{ A.}$