Thermal conductivity k is heat flow per unit

thickness, area and temperature difference

2066 Shrawan (old course) · 2 marks

Define thermal conductivity

Short answer

Thermal conductivity is the rate of heat flow through a unit thickness per unit area per unit temperature difference, given by Fourier's law. Low values (timber, cork) indicate good insulators; high values (steel, copper) indicate good conductors.

Define thermal conductivity as a property of materials, with sketch where necessary.

Thermal conductivity ( $k$ ) is the rate of heat flow through a unit thickness of a material, per unit area, per unit temperature difference between its faces. By Fourier's law:

Q = \frac{k\,A\,(T_1-T_2)\,t}{L}

where $Q$ is the heat conducted in time $t$ through a slab of area $A$ and thickness $L$ whose faces are at temperatures $T_1$ and $T_2$ . The unit of $k$ is W/(m·K). A low value means a good insulator (timber, cork, hollow bricks); a high value means a good conductor (steel, copper).

  T1 (hot)  +---------------+  T2 (cold)
   ======>  |  area A       |  ======>
   heat Q   +---------------+
            <------ L ------>

✓ Answer checked by Claude Opus 5.5 (high effort)

Important properties of civil engineering materials · Civil Engineering Materials, chapter 1 · asked 8×
Constituents of brick earth and functions · Civil Engineering Materials, chapter 3 · asked 9×
Define creep in brief · Civil Engineering Materials, chapter 1 · asked 8×
Fourier law and thermal conductivity · Heat Transfer, chapter 2
Plane wall with temperature dependent conductivity · Heat Transfer, chapter 2
Need of heat sink; thermal Ohm's law · Electronics Devices and Circuit, chapter 4
Thermal stress in a restrained bar · Strength of Materials, chapter 2

All Civil Engineering Materials chapter 1 questions →

Define thermal conductivity

Related questions