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Manipal MET2022PhysicsCurrent Electricity

The electric resistance of a wire is R . If the length of the wire is increased to doubled by stretching it, then the new resistance of the wire is

Options

  1. A2 R
  2. B4 R
  3. CR
  4. D16 R

Correct answer

B. 4 R

Step-by-step solution

aligned & As, R= L A = L^2 A L = L^2 V ;(V= Volume ) & R L^2 R₂ R₁ = ( L₂ L₁ )^2= ( 2 L₁ L₁ )^2=4 & R₂=4 R₁=4 R aligned

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