Navigate

A coil of self-inductance L is connected in series with a bulb B and an AC source

A coil of self-inductance L is connected in series with a bulb B and an AC source. Brightness of the bulb decreases when

Options

(a) number of turns in the coil is reduced
(b) a capacitance of reactance Xc = Xl is included in the same circuit
(c) an iron rod is inserted in the coil
(d) frequency of the AC source is decreased

Correct Answer:

an iron rod is inserted in the coil

Explanation:

By inserting iron rod in the coil, L ↑ z ↑ I ↓ so brightness ↓

NEET2013
admin:

Related Questions

  1. At what distance from the centre of earth, the value of acceleration due to gravity
  2. To measure the roughness of the surface of a material, which of the following microscope
  3. When the rate of flow of charge through a metallic conductor
  4. A thin film of soap solution (n=1.4) lies on the top of a glass plate (n=1.5).
  5. A car is moving with uniform acceleration. It covers 200 m in 2 sec and 220 m