How to derive it
Start from a formula that defines thermal conductivity, then replace each quantity with its dimensions. M is mass, L is length, T is time, K is temperature.
- Rearrange: K = (Q/t) × l ÷ (A ΔT)
- = [ML²T⁻³] × [L] ÷ ([L²] × [K])
- So [thermal conductivity] = [MLT⁻³K⁻¹], also written [M¹L¹T⁻³K⁻¹].
Dimensional formulas of other quantities
The full searchable list, with SI units, is on the dimensional formula page.
Questions students ask
What is the dimensional formula of thermal conductivity?
[MLT⁻³K⁻¹] (or [M¹L¹T⁻³K⁻¹]), from Q/t = KA ΔT ÷ l. Its SI unit is W m⁻¹ K⁻¹.
What are the dimensions of thermal conductivity?
M: 1, L: 1, T: -3, K: -1.
What is the SI unit of thermal conductivity?
W m⁻¹ K⁻¹.