Question

In the circuit shown in fig. R is a pure resistor, L is an inductor of ngligibe resistance (as compared to R), S is a 100 V , 50 Hz ac source of negligible resistnce. With either kiy `(K-1) `alone or `(K_2)` alone closed, the current is `(I_0)`. If the source os changed to 100 V, 100 Hz the current with `(K_1)` alone closed and with `(K_2)` alone closed will be, respectively.

A. `(I_0), (I_0)/(2)`
B. `(I_0), 2(I_0)`
C. `2(I_0), (I_0)`
D. `2(I_0),(I_0)/(2)`

Answer 1

Correct Answer - A
Current remains unchanged in R. However, it becomes half in L, because reactance is doubled on doubling the frequencuy.