Electricity and Magnetism MCQs

Tech Books Yard have 149 Electricity and Magnetism for Free Download

One of the common application of an air- cored choke.

  • A. Radio frequency
  • B. Audio frequency
  • C. Power supply
  • D. Power transformer
  • Correct Answer: Option A

The magnetic energy stored in an inductor is ______ current.

  • A. Directly proportional to
  • B. Inversely proportional to
  • C. Directly proportional to the square of
  • D. Inversely proportional to the square of
  • Correct Answer: Option C

The force between two magnetic poles is ____________ their poles strength.

  • A. equal to
  • B. directly proportional to
  • C. inversely proportional to
  • D. directly proportional to the square root of
  • Correct Answer: Option B

A t/m is a unit of

  • A. Mmf
  • B. Emf
  • C. Reluctance
  • D. Magnetizing force
  • Correct Answer: Option D

The permeability of permalloy is

  • A. Very much greater than permeability of air
  • B. Slightly greater than permeability of air
  • C. Slightly less than permeability of air
  • D. Equal to the permeability of air
  • Correct Answer: Option A

Which of the following is a paramagnetic material?

  • A. Carbon
  • B. Copper
  • C. Bismuth
  • D. Oxygen
  • Correct Answer: Option D

The core of a magnetic equipment uses a magnetic material with

  • A. Least permeability
  • B. Low permeability
  • C. Moderate permeability
  • D. High permeability
  • Correct Answer: Option D

Magnetic intensity is a

  • A. Phasor quantity
  • B. Physical quantity
  • C. Scalar quantity
  • D. Vector quantity
  • Correct Answer: Option D

Residual magnetism refers to the flux density, which exists in the iron core when the magnetic field intensity is

  • A. Minimized
  • B. Reduced to zero
  • C. Maximize
  • D. Unity
  • Correct Answer: Option B

How many electrons are needed in the valence orbit to give a material’s stability?

  • A. 8
  • B. 4
  • C. 6
  • D. 5
  • Correct Answer: Option A