Orbits and orbital speed
Why gravity keeps moons, planets and satellites in orbit, how the velocity can change while the speed stays the same, why closer orbits are faster, and calculating orbital speed with v = 2πr/T.
You will be able to
- Explain how gravity changes the velocity but not the speed in a circular orbit
- Explain why a stable orbit at a smaller radius needs a higher speed
- Calculate orbital speed, period or radius with v = 2πr/T, converting km, hours, days and years
25 minutes, 9 exam-style questions, with the Orbits simulation.