Question

A power transformer is used to step up an alternating e.m.f. of 220 V to 11 kV to transmit 4.4 kW of power. If the primary coil has 1000 turns, what is the current rating of the secondary? Assume 100% efficiency for the transformer

• A. 4 A
• B. 0.4 A
• C. 0.04 A
• D. 0.2 A

Answer 1

Answer: (B)

0.4 A

Answer 2

$i_{s} = \frac{P_{s}}{V_{s}} = \frac{4.4 \times 10^{3}}{11 \times 10^{3}} = 0.4\mspace{6mu} A$