Temperature has a direct effect on the expansion of solids. Here’s how it works:
- When the temperature of a solid increases, its particles gain kinetic energy and start vibrating more vigorously.
- These increased vibrations cause the particles to move slightly further apart on average.
- As a result, the solid expands—its dimensions (length, area, and volume) increase.
- Conversely, when the temperature decreases, particles vibrate less and come closer together, causing the solid to contract.
This phenomenon is called thermal expansion.
Key points:
- The amount a solid expands depends on the material and the temperature change.
- For most solids, the expansion is approximately proportional to the change in temperature.
- The relation for linear expansion is often given by: ΔL=αL0ΔT\Delta L = \alpha L_0 \Delta T where:
- ΔL\Delta L = change in length,
- L0L_0 = original length,
- ΔT\Delta T = change in temperature,
- α\alpha = linear expansion coefficient (a material-specific constant).
So, higher temperature → expansion, lower temperature → contraction.