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

1. MLT²K
2. ML⁻³K
3. MLT⁻³K⁻¹
4. MLT⁻²K⁻²

Correct answer: MLT⁻³K⁻¹

Solution

From Q = k A (dT) t / d, k = Q d/(A dT t) = (ML^2T^-2 * L)/(L^2 * K * T) = M L T^-3 K^-1.

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