MCQ
Dimensional formula for thermal conductivity is (here $K$ denotes the temperature)
- A$MLT ^{-3} K$
- B$MLT ^{-2} K$
- C$ML T ^{-2} K ^{-2}$
- ✓$MLT ^{-3} K ^{-1}$
✓
Answer
Correct option: D.
$MLT ^{-3} K ^{-1}$
d
$\because \frac{ d Q}{ dt }= k A \frac{ d T }{ d x }$
$\because \frac{ d Q}{ dt }= k A \frac{ d T }{ d x }$
$k =\frac{\left(\frac{ d Q}{ dt }\right)}{ A \left(\frac{ d T }{ d x }\right)}$
$[ k ]=\frac{\left[ ML ^{2} T ^{-3}\right]}{\left[ L ^{2}\right]\left[ KL ^{-1}\right]}=\left[ MLT ^{-3} K ^{-1}\right]$
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