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NEET2021PhysicsCurrent ElectricityActual

The effective resistance of a parallel connection that consists of four wires of equal length, equal area of cross-section and same material is 0 . 25   Ω . What will be the effective resistance if they are connected in series?

Options

  1. A0 . 25   Ω
  2. B0 . 5   Ω
  3. C4   Ω
  4. D1   Ω

Correct answer

C. 4   Ω

Step-by-step solution

Let the resistance of each wire be R Effective resistance in parallel combination, R P = R 4 ⇒ R = 4 R P ⇒ R = 4 × 0 . 25 = 1   Ω Effective resistance is series combination, R S = 4 R ⇒ R s = 4 × 1 = 4   Ω

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