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 mm long at a temperature of 20 ∘C∘C. What is its length on a hot summer day when the temperature is 35 ∘C∘C?

Two students, each riding bicycles, start from the same apartment building and ride to the same building on campus, but each takes a different route. the first student rides 1100 m due east and then turns due north and travels another 1430 m before arriving at the destination. the second student heads due north for 1930 m and then turns and heads directly toward the destination. at the turning point, how far is the second student from the destination?