Electro Magnetic Induction And Alternating Currents Question 299
Question: Assertion : The back emf in a dc motor is maximum when the motor has just been switched on. Reason : When motor is switched on it has maximum speed.
Options:
A) If both assertion and reason are true and the reason is the correct explanation of the assertion.
B) If both assertion and reason are true but reason is not the correct explanation of the assertion.
C) If assertion is true but reason is false.
D) If the assertion and reason both are false.
E) If assertion is false but reason is true.
Show Answer
Answer:
Correct Answer: D
Solution:
Backs emf. $ e\propto \omega $ . At start w = 0 so e = 0