Indirect Measurement Lab
How Tall is the Water Tower?
Earlier in the year the 8th grade math class studied similar figures and how to use proportions to find missing dimensions. The weather finally cooperated for our lab, so to help illustrate this concept, 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. Here are some sample calculations. If more than one group measured an object, we found the average.
Water Tower 30.2 m
Wells Pine Tree 19 m
High School Building 10.6 m
Light Pole 10.2 m