Electro Magnetic Induction And Alternating Currents Question 262
Question: A step-down transformer is connected to main supply 200V to operate a 6V, 30W bulb. The current in primary is [AMU (Engg.) 1999]
Options:
A) 3 A
B) 1.5 A
C) 0.3 A
D) 0.15 A
Show Answer
Answer:
Correct Answer: D
Solution:
$ V_{p}=200\ V,\ \ V_{s}=6V $
$ P_{out}=V_{s}i_{s}\Rightarrow 30=6\times i_{s}\Rightarrow i_{s}=5\ A $
From $ \frac{V_{s}}{V_{p}}=\frac{i_{p}}{i_{s}}\Rightarrow \frac{6}{200}=\frac{i_{p}}{5}\Rightarrow i_{p}=0.15\ A $
