Physics

Problem

Which of the following expressions gives the rate of energy transfer

\frac{Q}{\Delta t}

through a uniform slab of thickness

L

, cross-sectional area

A

, and temperature difference

\Delta T

across its faces? (All symbols have their usual meanings.) a)

\displaystyle \frac{k\,A}{L\,\Delta T}

\displaystyle \frac{k\,A\,\Delta T}{L}

\displaystyle \frac{k\,L\,\Delta T}{A}

\displaystyle \frac{k\,A\,\Delta T}{2L}