A load is connected across the secondary of the step up transformer shown in figure "B" of the illustration and the current drawn by the load is 10 amps. If the turns ratio is 1 to 10 and the input voltage is 110 VAC, what will be the current drawn by the primary? Illustration EL-0055

Correct Answer: Option B — 100 amps

Transformer power remains constant (neglecting losses), expressed as $V_p I_p = V_s I_s$. With a 1:10 turns ratio, secondary current is stepped down while primary current is stepped up by a factor of 10. Thus, a 10A secondary load draws $10 \times 10 = 100$ amps on the primary.