Electro Magnetic Induction And Alternating Currents Question 605
Question: A solenoid has an inductance of 60 henrys and a resistance of 30 ohms. If it is connected to a 100 volt battery, how long will it take for the current to reach $ \frac{e-1}{e}\approx 63.2% $ of its final value [MP PET 2000]
Options:
A) 1 second
B) 2 seconds
C) e seconds
D) 2e seconds
Show Answer
Answer:
Correct Answer: B
Solution:
$ t=\tau =\frac{L}{R}=\frac{60}{30}=2,\sec . $
