Electro Magnetic Induction And Alternating Currents Question 4

Question: An alternating e.m.f. is applied to purely capacitive circuit. The phase relation between e.m.f. and current flowing in the circuit is or In a circuit containing capacitance only [MP PET 1996; AIIMS 1997]

Options:

A) e.m.f. is ahead of current by $\frac{\pi}{2}$

B) Current is ahead of e.m.f. by $\frac{\pi}{2}$

C) Current lags behind e.m.f. by $\pi$

D) Current is ahead of e.m.f. by $\pi$

Show Answer

Answer:

Correct Answer: B

Solution:

For purely capacitive circuit $ e=e_{0}\sin \omega t $ $ i=i_{o}\sin ( \omega t+\frac{\pi }{2} ) $ i.e. current is ahead of emf by $ \frac{\pi }{2} $