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Current Electricity question

2022 · 29 Jul · Shift 1 · Q59
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Current Electricity question

2022 · 29 Jul · Shift 1 · Q59

JEE MainPhysicsCurrent ElectricityMCQ+4 / −1
Two metallic wires of identical dimensions are connected in series. If σ1\sigma_{1}σ1​ and σ2\sigma_{2}σ2​ are the conductivities of the these wires respectively, the effective conductivity of the combination is :
  1. A
    σ1σ2σ1+σ2\frac{\sigma_{1} \sigma_{2}}{\sigma_{1}+\sigma_{2}}σ1​+σ2​σ1​σ2​​
  2. B
    2σ1σ2σ1+σ2\frac{2 \sigma_{1} \sigma_{2}}{\sigma_{1}+\sigma_{2}}σ1​+σ2​2σ1​σ2​​
  3. C
    σ1+σ22σ1σ2\frac{\sigma_{1}+\sigma_{2}}{2 \sigma_{1} \sigma_{2}}2σ1​σ2​σ1​+σ2​​
  4. D
    σ1+σ2σ1σ2\frac{\sigma_{1}+\sigma_{2}}{\sigma_{1} \sigma_{2}}σ1​σ2​σ1​+σ2​​
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