Global positioning systems and Magnetic Compasses
Object: To show the student how practical this technology is and not just for sailing. Compare using it with a magnetic compass
Materials: Handheld GPS unit (unit with road maps already programmed is desirable)
Video on its use (Usually available along with unit)
Magnetic Compass and book on orienteering
Topographical map of school area
Show video and discuss how the accuracy is affected by the satellites' position relative to your location.
Discuss how magnetic compass works and how to locate yourself on the map using the principles discussed in orienteering.
Divide the class into two groups. One group will use the GPS unit. The other group will use the compass.
Give each group a predetermined route to follow around the schoolyard. Tell the groups they will switch and then compare how easy or hard each approach is to use. Let the whole group see how the satellites change position with the GPS held stationary.
Discuss why the satellites stay in orbit around the Earth just as the Moon does. Relate how Newton made the connection between the falling apple and the falling Moon.
Discuss the relationship between the Moons period and the satellites periods and their distance from the Earth using Kepler’s laws.
Discuss what position the magnetic compass would point to at the magnetic north pole.
Lesson plan by Ray Manning First Baptist Church School