By combining Newton's Universal Law of Gravity with the centripetal
force that causes an object to move in a circle, we can solve the equation
for "r". Then, the
altitude is determined by subtracting the radius of Earth, Eradius,
from the total distance of the satellite from Earth's center, "r".
|
Newton's Universal Law of Gravity |
Central Force Causing an Object to Move in a Circle |
Altitude, Hheight |
| Fgravity=Gm Earthmsatellite
/ r2
equation 1 |
Fcircl = msatellite v2
/ r
equation 2 |
Hheight = r
- Eradius
equation 3 |
| G = 6.672 X 10-11 Nm2/kg2
mEarth = 5.98 X 1024 kg r = distance of satellite from center of Earth |
velocity, v = 2pr
/ t
period, t = time to orbit Earth once (from Part I) |
Eradius = 3960 X 103 m |
First, set Fgravity = Fcircle (i.e.,
set equation 1 equal to equation
2). Second, solve the equation algebraically for the distance
that the satellite orbits from the center of Earth, r.
Finally, determine the altitude, Hheight from equation
3. Determine the altitude of the Yohkoh spacecraft.
Back
to the Orbital Velocity or onward to Satellite
Network Monitoring 
Lesson designed by the YPOP
Team
For questions about this lesson, please contact
Tim Slater