Electro Magnetic Induction And Alternating Currents Question 215
Question: A transformer having efficiency of 90% is working on 200V and 3kW power supply. If the current in the secondary coil is 6A, the voltage across the secondary coil and the current in the primary coil respectively are:
Options:
A) 300V, 15A
B) 450V, 15A
C) 450V, 13.5A
D) 600V, 15A
Show Answer
Answer:
Correct Answer: B
Solution:
-
Efficiency $ \eta =\frac{V_{s}I_{s}}{V_{p}I_{p}}\Rightarrow 0.9=\frac{V_{s}(6)}{3\times 10^{3}}\Rightarrow V_{s} $ = 450V
As $ V_{P}I_{p}=3000 $
So $ I_{p}=\frac{3000}{V_{p}}=\frac{3000}{200}=A=15A $
