How does heat travel through a metal bar?
Heat equation
How does heat travel through a metal bar?
Imagine you're holding a metal rod with one end in a flame and the other end in ice water. Over time, the heat from the flame moves through the rod and eventually reaches the ice water.
Heat spreads out from the hot end to the cold end because particles in the hot region gain energy and move faster, bumping into neighboring particles and transferring some of their energy along the way. This process continues until the heat is evenly distributed. The underlying principle is described by the heat equation, a parabolic partial differential equation.
Example
If the rod is 1 meter long and initially 100°C at the hot end, after a while, the temperature at the ice water end will rise from 0°C to a higher value as heat diffuses through the rod.
Remember this
The heat equation explains how temperature changes over time and space in a material.
Text adapted from Wikipedia, licensed under CC BY-SA 4.0.
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