Prostuti360°Prostuti360°
Log in

WBCS Main Examination 2023 — Paper IV: General Studies II · Question 7 of 200

Q7
General SciencePhysics
A magnetic field can be produced by
  1. a.moving charge.
  2. b.a changing electric field.
  3. c.both (A) and (B)
  4. d.None of the above

Answer: (C) both (A) and (B)

A moving charge (an electric current) produces a magnetic field, and by Maxwell's displacement-current idea a changing electric field also produces one. Since both sources work, the answer is (C); choosing only (A) or (B) leaves out the other.

Q6 Whole paperQ8