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The unit of thermal conductivity is:...

The unit of thermal conductivity is:

A

`W m^(-1) K^(-1)`

B

`J mK^(-1)`

C

`J m^(-1) K^(-1)`

D

`W mK^(-1)`

Text Solution

Verified by Experts

The correct Answer is:
A
`(d Q)/(dt) = kA (dT)/(dx)`
`:. K= ((dQ)/(dt))/(A xx (dT)/(dx))`
`:.` Unit of k
`= (""_(J)//""_(S))/(m^(2) xx ("kelvin")/(m))`
`= (W)/(m xx "kelvin")`
`=W m^(-1) K^(-1)`
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