Question

Assertion: A bulb connected in series with a solenoid is connected to `AC` source. If a soft iron core is introduced in the solenoid, the bulb will glow brighter.
Reason: On introducing soft iron core in the solenoid, the inductance increases.
A. If both the assertion and reason are true and reason is a true explantion of the assertion.
B. If both the assertion and reason are true but the reason is not true the correct explantion of the assertion.
C. If the assertion is true but reason false
D. If assertion false but reason is true.

Answer 1

Correct Answer - D
On introducing soft iron core, the bulb will glow dimmer. This is because on introducing soft iron core in the solenoid, its inductance `L` increases, the inductive reactance, `X_(L)=omegaL` increases and hence the current through the bulb decreases.