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NEET2007PhysicsCurrent ElectricityActual

When a wire of uniform cross-section a , length l and resistance R is bent into a complete circle, resistance between two of diametrically opposite points will be

Options

  1. AR 4
  2. BR 8
  3. C4 R
  4. DR 2

Correct answer

A. R 4

Step-by-step solution

When wire is bent to form a complete circle then 2 r=R r= R 2 Resistance of each semicircle = r= R 2 = R 2 Thus, net resistance in parallel combination of two semicircular resistance R^ = R 2 R 2 R 2 + R 2 = R^2 4 R = R 4

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