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JEE Main202116 Mar 2021Evening ShiftPhysicsMagnetic Effects of CurrentActual

A charge Q is moving d l → distance in the magnetic field B → . Find the value of work done by B → .

Options

  1. A1
  2. BInfinite
  3. CZero
  4. D- 1

Correct answer

C. Zero

Step-by-step solution

Since force on a point charge by magnetic field is always perpendicular to v → F → = q v → × B → ∴ Work by magnetic force on the point charge is zero.

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