Physics · 2021
JEE Main · 17 March 2021, Shift 1 · Q11
Two identical metal wires of thermal conductivities K_1 and K_2 respectively are connected in series. The effective thermal conductivity of the…
Two identical metal wires of thermal conductivities $\displaystyle \mathrm{K}_1$ and $\displaystyle \mathrm{K}_2$ respectively are connected in series. The effective thermal conductivity of the combination is :
Official answer
(2)
$\displaystyle \frac{2 \mathrm{~K}_1 \mathrm{~K}_2}{\mathrm{~K}_1+\mathrm{K}_2}$
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JEE Main 2021 Physics question, with the answer from NTA’s final answer key. Where our answers come from.