In order to complete this project, you will need a meter stick or some other object and a tape measure.
At least every other week, as close to noon as possible*, go outside on a sunny day (or any day during
which you can see your shadow). Holding the meter stick (or any object) upright, mark the end points of
its shadow. Measure the length of the shadow. Based on this length and the height of the object casting
the shadow, you can determine the altitude of the Sun.
(*Between the first Sunday in April and the last Sunday in October, “noon” will actually be at 1:00PM
due to daylight savings.)
The altitude of the Sun is simply a measurement of how high it appears above the horizon, in terms of an
angular measurement. If the Sun were directly overhead, it would be at an altitude of 90o
(since a full circle is 360o, and from the horizon to directly overhead is one-quarter
of a full circle). As you can see from the picture, the altitude of the Sun is related to the length
of the stick and the length of the stick’s shadow by the formula:
or, the altitude of the Sun can be determined by taking the inverse tangent of the ratio of the height
of the stick to the length of its shadow:
- At least every other week (it would be good if you could space your measurements out evenly throughout
the semester), measure the altitude of the Sun (you need to take all of your measurements from the same
general location/town and use the same measurement stick for all measurements).
Record your measurements in the table below.
- After you have completed your observations, plot your results on the graph provided.
- Worksheet to be handed in