Physics-
General
Easy
Question
A circuit consisting of a constant e.m.f. 'E', a self-induction 'L' and a resistance 'R' is closed at t = 0. The relation between the current I in the circuit and time t is as shown by curve 'a' in the figure. When one or more of parameters E, R & L are changed, the curve 'b' is obtained. The steady state current is same in both the cases. Then it is possible that
- E & R are kept constant and L is increased.
- E & R are kept constant and L is decreased
- E & R are both halved and L is kept constant
- E & L are kept constant and R is decreased
The correct answer is: E & R are kept constant and L is increased.
Since curve 'b' is below curve 'a' hence it is possible that E & R are kept constant and L is increased or E & R are both halved and L is kept constant
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