A steel railroad track has a length of 33 m when the temperature is −2 ◦C. What is the increase in the length of the rail on a hot day when the temperature is 39 ◦C? The linear expansion coefficient of steel is 11 × 10−6 ( ◦C)−1 . Answer in units of m.

0.0149 m

Explanation:

When a solid material is heated, it expands; in particular, its length increases according to the equation:

where

is the increase in length

is the linear expansion coefficient

is the original length of the material

is the increase in temperature

In this problem:

is the original length of the steel railroad track

is the linear expansion coefficient of steel

is the change in temperature of the track

Therefore, the increase in length is: