Indirect Measurement Lab
How Tall is the Water Tower?
In 8th grade math class we have been studying similar figures and using proportions to find missing dimensions. To help illustrate this concept with an application, I asked the students how we could determine the height of the water tower without actually climbing it. Though I had several volunteers willing to scale the tower, that was clearly not an option. Using the known height of a student and the lengths of the shadows, we created similar triangles and calculated the height of the water tower and several other tall objects. The weather finally cooperated for us and we had a nice sunny morning to take our measurements. Here are some sample calculations. If more than one group measured an object, we found the average.
Water Tower 31.4 m
Wells Pine Tree 17.2 m
Flagpole 8.8 m
Basketball Hoop 3.8 m