engineering recuitment BARC Stipendiary Trainee Category I 2023 Mock Test Physics Current, Resistance and Electricity Resistance and Resistivity
Two identical metal wires of thermal conductivities K1 and K2 respectively are connected in series. The effective thermal conductivity of the combination is:
1
\(\frac{K_1 K_2}{K_1 + K_2}\)
2
\(\frac{2K_1 K_2}{K_1 + K_2}\)
3
\(\frac{K_1+ K_2}{2K_1 K_2}\)
4
\(\frac{K_1+ K_2}{K_1 K_2}\)