Electro Magnetic Induction And Alternating Currents Question 560
Question: If the current is halved in a coil, then the energy stored is how much times the previous value [CPMT 1999]
Options:
A) $ \frac{1}{2} $
B) $ \frac{1}{4} $
C) 2
D) 4
Show Answer
Answer:
Correct Answer: B
Solution:
$ U=\frac{1}{2}Li^{2}\ i.e.\frac{U_{2}}{U_{1}}={{( \frac{i_{2}}{i_{1}} )}^{2}}={{( \frac{1}{2} )}^{2}}=\frac{1}{4} $
$ \Rightarrow U_{2}=\frac{1}{4}U_{1} $
