QHST Reaches new heights?

Last week's lab had students go outside and measure the height of QHST using their distance from the building and the angle to the top of the building (measured by use of a simple hypsometer made from a protractor, string and a couple of washers). Trigonometry lets you use one side and an angle to fins all other sides and angles.

The height of the building at the point measured (at the top of the South stairway) is approximately 91 feet.

What if you only had a barometer, paper and pencil - could you still measure the height of the building? These guys did. Note that they first used physics to get the answer. Before you click the link - could you think of a simple method done without trigonometry?