Physics · 2015
NEET 2015 · 25 July · Code C · Q15
Two metal wires of identical dimensions are connected in series. If σ_1 and σ_2 are the conductivities of the metal wires respectively, the effective…
Two metal wires of identical dimensions are connected in series. If $\displaystyle \sigma_1$ and $\displaystyle \sigma_2$ are the conductivities of the metal wires respectively, the effective conductivity of the combination is :
Official answer
From NTA’s final answer key for this paper.
(3)
$\displaystyle \frac{2 \sigma_1 \sigma_2}{\sigma_1+\sigma_2}$
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NEET (UG) 2015 Physics question, with the answer from NTA’s final answer key. Where our answers come from.