Two rods of crossectional area $A$ and $2A$ and equal length having thermal conductivities $2K$ and $3K$ are joined in parallel, then equivalent thermal conductivity of their combination will be-
Two rods of crossectional area $A$ and $2A$ and equal length having thermal conductivities $2K$ and $3K$ are joined in parallel, then equivalent thermal conductivity of their combination will be-
- A
$\frac{5K}{3}$
- B
$\frac{8K}{3}$
- C
$\frac{11K}{3}$
- D
$\frac{13K}{3}$
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