Question

Dimensional formula for thermal conductivity is (here $K$ denotes the temperature)

• A. $MLT ^{-3} K$
• B. $MLT ^{-2} K$
• C. $MLT ^{-2} K ^{-2}$
• D. $MLT ^{-3} K ^{-1}$

Answer 1

Answer: (D)

$MLT ^{-3} K ^{-1}$

Answer 2

$\because \frac{ d \theta}{ dt }= kA \frac{ dT }{ d x }$
$k =\frac{\left(\frac{ d \theta}{ dt }\right)}{ A \left(\frac{ dT }{ d x }\right)}$
$[ k ]=\frac{\left[ ML ^{2} T ^{-3}\right]}{\left[ L ^{2}\right]\left[ KL ^{-1}\right]}$
$=\left\lfloor ML T ^{-3} K ^{-1}\right\rfloor$