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A magnetised wire of moment M and length l is bent in the form of a semicircle of radius r . Then its new magnetic moment is

Options

  1. A2 M π
  2. B2 M
  3. CM π
  4. Dzero

Correct answer

A. 2 M π

Step-by-step solution

On bending a wire its pole strength remains unchanged whereas its magnetic length changes. New magnetic moment, M ' = m × 2 r = m × 2 l π = 2 M π

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