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_JEE_MAIN_2021
170321_S1
Question
Two identical metal wires of thermal conductivities K1 and K2 respectively are connected in series. The effective thermal conductivity of the combination is :
Select the correct option:
A
$\frac{2 \mathrm{~K}_1 \mathrm{~K}_2}{\mathrm{~K}_1+\mathrm{K}_2}$
B
$\frac{K_1+K_2}{2 K_1 K_2}$
C
$\frac{\mathrm{K}_1+\mathrm{K}_2}{\mathrm{~K}_1 \mathrm{~K}_2}$
D
$\frac{\mathrm{K}_1 \mathrm{~K}_2}{\mathrm{~K}_1+\mathrm{K}_2}$
✓ Correct! Well done.
✗ Incorrect. Try again or view the solution.
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