Two rods of equal length and diameter but of thermal conductivities 1.5 and 3 S.I. units respectivity of combination is :

Two rods of equal length and diameter but of thermal conductivities 1.

1.	Two rods of equal length and diameter but of thermal conductivities 1.5 and 3 S.I. units respectivity of combination is :
Answer» `2.5` 2 `2.25` `4.5` SOLUTION :In SERIES `k=(2k_(1)k_(2))/(k_(1)+k_(2))=(2xx1.5xx3)/(3+15)=2`. Thus correct choice is (b).

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Two rods of equal length and diameter but of thermal conductivities 1.5 and 3 S.I. units respectivity of combination is :

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