Q. A current of 5 A is flowing at 220 V in the primary coil of a transformer. If the voltage produced in the secondary coil is 2200 V and 50% of power is lost, then the current in secondary will be
A) 2.5 A
B) 5 A
C) 0.25 A
D) 0.5 A
Explanation
(c) $V_{P} = 220V,\ V_{S} = 2200\ V,\ I_{P} = 5\ A,\ I_{S} = ?$
Power loss=50%
Efficiency of transformer $(\eta)$ is defined as the ratio of output power and input power.
$ie,\ \ \eta\% = \frac{P_{out}}{P_{in}} \times 100 = \frac{V_{S}I_{S}}{V_{P}I_{P}} \times 100$
$\ \ \ \ \ \ \ \ \ \ \ \ \ \ 50 = \frac{2200 \times I_{S}}{220 \times 5} \times 100$
$\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ I_{S} = 0.25A$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.