If both the resistance and the inductance in an LR AC series circuit are doubled

If both the resistance and the inductance in an LR AC series circuit are doubled the new impedance will be

Options

(a) halved
(b) fourfold
(c) doubled
(d) quadrupled

Correct Answer:

doubled

Explanation:

For L-R circuit, Z = √(R² + Xʟ²)

Z₁ = √(R₁² + Xʟ₂²)

Z₂ = √(R₂² + Xʟ₂²)

Given, R₂ = 2R and Xʟ₂ = 2Xʟ

Then, Z₂ = √[(2R)² + (2Xʟ)²] = 2 Z₁

admin:

Related Questions

  1. Order of e/m ratio of proton, α-particle and electron is
  2. If 10000 V is applied across an X-ray tube, what will be the ratio of de-Broglie
  3. A lens having focal length f and aperture of diameter d forms an image of intensity I
  4. When a wire of uniform cross-section a, length l and resistance R
  5. If longitudinal strain for a wire is 0.03 and its poisson’s ratio is 0.5