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AP EAMCET202317 May 2023Morning ShiftPhysicsCurrent ElectricityActual

Two metal wires of same length, same area of crosssection have conductivities of their material ₁ and ₂ . If they are connected in series, the effective conductivity is

Options

  1. A₁ ₂ ₁+ ₂
  2. B2 ₁ ₂ ₁+ ₂
  3. C₁ ₂ ₁- ₂
  4. D₁ ₂ ₁- ₂

Correct answer

B. 2 ₁ ₂ ₁+ ₂

Step-by-step solution

If they are connected in series, then aligned & R_ e q =R₁+R₂ & L+L _ e q A = L ₁ A + L ₂ A & 2 _ e q = 1 ₁ + 1 ₂ _ e q = 2 ₁ ₂ ₁+ ₂ aligned

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