MCQ
A magnetic field can be produced by:
  • A
    A moving charge.
  • B
    A changing electric field.
  • C
    None of these.
  • D
    Both of these.

Answer

  1. Both of these.

Explanation:

A moving charge and changing electric field both produces magnetic field.

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A magnetic field can be produced by:
  1. A moving charge.
  2. A changing electric field.
  3. Neither of them.
  4. Both of them.

Huygen wave theory allows us to know

(a) The wavelength of the wave

(b) The velocity of the wave     

(c) The amplitude of the wave

(d) The propagation of wave fronts