Question

A transformer has $500$ primary turns and $10$ secondary turns. If the secondary has a resistive load of $15\, \Omega$ the currents in the primary and secondary respectively, are

• A. $0.16 A , 3.2 \times 10^{-3} A$
• B. $3.2 \times 10^{-3} A , 0.16 A$
• C. $0.16 A , \times 0.16 A$
• D. $3.2 \times 10 .^{-3} A , 3.2 \times 10^{-3} A$

Answer 1

Answer: (B)

We have, $\frac{N_{S}}{N_{P}}=\frac{i_{P}}{I_{S}} \frac{10}{500}=\frac{i_{S}}{i_{S}}$ $\Rightarrow \frac{i_{P}}{i_{S}}=\frac{1}{50}$
$\Rightarrow i_{s}=50 i_{p}$
This condition is satisfied only when current in primary
$3.2 \times 10^{-3} A$ and in secondary $0.16\, A$.