A transformer has 400 turns on the primary and 100 turns on the secondary. A $220,\text{V rms}$ sinusoidal supply at $50,\text{Hz}$ is connected to the primary. The secondary is connected to a resistive load of $200,\Omega$. Find (i) the secondary rms voltage and (ii) the secondary rms current.

Step-by-step solution

1. Use the transformer turns ratio: $\frac{V_s}{V_p}=\frac{N_s}{N_p}$.
2. Calculate $V_s=220\times \frac{100}{400}=55,\text{V}$ for the secondary rms voltage.
3. Use Ohm’s law on the secondary: $I_s=\frac{V_s}{R_{\text{load}}}=\frac{55}{200}=0.275,\text{A}$ for the secondary rms current.

Concept tested: Transformer voltage and current relations

Published 9 September 2026 · Last updated 16 September 2026 · How this solution was prepared and checked