# Question 1: Group Activity

1. A geosynchronous satellite is a satellite which orbits the earth with an orbital period of 24 hours, thus matching the period of the earth's rotational motion. A special class of geosynchronous satellites is a geostationary satellite.

A geostationary satellite orbits the earth in 24 hours along an orbital path which is parallel to an imaginary plane drawn through the Earth's equator. Such a satellite appears permanently fixed above the same location on the Earth. For a geostationary satellite to orbit the earth once in 24 hours (86400 s), how high (in meters) above the earth's surface must it be located?

 Given/Known: T = 24 h = 86400 s Mearth = 5.98x1024 kg Rearth = 6.37 x 106 m G = 6.67 x 10-11 N m2/kg2 Angular Velocity of Earth = 7.292 x 10 -5s -1 Unknown: h = ??? Hint: The unknown in this problem is the height of the satellite above the surface of the earth. Yet there is no equation with the variable h. The solution then involves first finding the radius of orbit and using this R value and the R of the earth to find the height of the satellite above the earth. As shown in the diagram at the right, the radius of orbit for a satellite is equal to the sum of the earth's radius and the height above the earth. The radius of orbit can be found using the following equation:

Rorbit = h + Rearth

## Working in Groups

We'll be dividing students up into working groups during the semester. Here's the group setup for this particular problem. We'll be rotating this as we move from exercise to exercise during the semester.

The meteorologists in this class have had much more background than have had the geologists, simply because of the course sequencing. While the oceanographers may have had physical oceanography, the meteorologists have had Metr 410 and Metr 430. Hence, we've had to structure the course to take advantage of this background by expecting the meteorologists to help more in the group discussions.

At this point, the function of the Group Leader is simply to start the discussions and to make sure the problem solving stays on track.

 Leader Yilin Lu Geoff Roest Ryan Thorp Group Makeup Craig Arsedo Emily Parker Sierra Brune Andrew Dotson Hannah Mewhirter John Ball Malori Redman