When discussing the expansion or contraction of materials with changes in temperature, the coefficient of linear expansion is crucial. It's a number that tells us how much a material will expand or contract per degree of temperature change. This coefficient is specific to each material. In the case of the penny made from a zinc alloy, the coefficient is given as \(2.6 \times 10^{-5} \, K^{-1}\).
This means for every degree Celsius (or Kelvin) the temperature changes, the alloy will expand or contract by \(2.6 \times 10^{-5}\) times its original size. It's important to note that this coefficient always relates to linear dimensions, such as length or diameter, rather than area or volume.
- The coefficient of linear expansion is represented by the Greek letter alpha (\(\alpha\)).
- It is a small value for most materials, signifying that only minor changes in size usually occur with temperature changes.
- An understanding of \(\alpha\) aids in predicting how structures might behave under different temperatures, ensuring safety and functionality.