Physics - Satellites
OCR A-Level Physics 2022
Flashcards
Orbital speed
What speed must a satellite be going at to orbit a planet at radius $r$?
\[\sqrt{\frac{GM}{r}}\]
Geostationary orbits
What three things must be true for a geostationary satellite?
- It must be in an orbit above the Earth’s equator.
- It must rotate in the same direction as the Earth’s rotation.
- It must have an orbital period of 24 hours.
Polar orbits
Why are polar orbits useful?
Because the earth rotates underneath them giving the satellite a complete view of the surface.
Orbital radius and period
What is true about orbits close to the Earth compared to those further away?
The close ones have a shorter period.