In this example, we see how thermal expansion can actually throw off the accuracy of a length-measuring device—namely, a tape measure. A surveyor uses a steel measuring tape that is exactly 50.000 m long at a temperature of 20 ?C. What is its length on a hot summer day when the temperature is 35 ?C?

A concrete slab forming part of a driveway is 10.000 mm long when the temperature is 20 ?C?C. How much does the driveway increase in length when the temperature increases to 30 ?C?C? The coefficient of linear expansion for concrete is 1.2×10?5K?11.2×10?5K?1.

=_______________mm