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A thin bar magnet of length 2L is bent at the mid-point so that the angle between them is 60 o . The new length of the magnet is

Options

  1. AL 2 3
  2. B3 L 2
  3. CL
  4. D2 L 3

Correct answer

C. L

Step-by-step solution

On bending the magnet, the angle between two parts of the magnet is expressed in diagram below Now, the minimum distance between the ends P and R = L sin ⁡ 30 o + L sin ⁡ 30 o = 2 L sin ⁡ 30 o   = 2 L sin ⁡ 30 o = 2 L × 1 2 = L

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