Navigate

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

KL2013
admin:

Related Questions

  1. In an LCR circuit, capacitance is changed from C to 2C. For the resonant frequency
  2. If fundamental frequency of closed pipe is 50 Hz then frequency of 2nd overtone
  3. A proton of mass 1.6×10⁻²⁷ kg goes round in a circular orbit of radius 0.10 m under
  4. A total charge of 5µC is distributed uniformly on the surface of the thin walled
  5. Frequency of stretched string will increase by