Satellites: orbital speed and period
Grade 11 Science Worksheet
Circle the best answer, or write your answer on the line.
Earth's GM is 398,600 km³/s² and its radius is 6371 km. For a model satellite 2000 km up, what is the orbital speed to the nearest hundredth, Esme?
The ISS's height varies between 370 and 460 km. How does its orbital speed change across that range, Jun?
- Its speed stays the same
- It is a little faster at 370 km
- It is a little faster at 460 km
Thin air drags on the ISS and slowly lowers its orbit. What must its engines do now and then, Kira?
- Nothing, since it rises again by itself
- Boost it back up
- Slow it down so it stays up
Two model satellites orbit at 370 km and 460 km. Which takes less time per orbit, Luz?
- They take the same time
- The one at 370 km
- The one at 460 km, since higher orbits are faster
NASA gives the Moon's orbit a semimajor axis of 384,400 km. About how far does the Moon travel in one orbit, Milo?
- About 384,400 km
- About 2.4 million km
- About 1.2 million km
The Moon travels about 2,415,000 km per orbit in 27.32 days (NASA). What is its average speed, Noah?
- About 0.01 km/s
- About 1.02 km/s
- About 88,400 km/s, treating days as seconds
Why is the Moon's orbital speed, 1.022 km/s, so much lower than the ISS's, Pia?
- It is much farther from Earth's center
- It has no engines
- Earth's pull stops partway to the Moon
A 1 kg and a 100 kg model satellite orbit at the same height. How do their speeds compare, Ren?
- The 100 kg one is faster
- They are the same
- The 1 kg one is faster
Why doesn't the satellite's own mass appear in v = √(GM ÷ r), Tala?
- Satellites have too little mass to count
- It cancels: the pull and the force needed both grow with it
- Mass doesn't matter in space
In v = √(GM ÷ r) for a satellite around Earth, what is M, Zee?
- The satellite's mass
- The Moon's mass
- Earth's mass