Physics · Lesson Worlds
Orbits: interactive science lab
Change the launch speed and prove that an orbit is a fall that keeps missing the ground.
Free · No account required · Runs in your browser
What will you learn?
Too slow, it falls in. Too fast, it leaves. The right speed is a fall that never finishes — an orbit.
How does the lab work?
Observe the simulation, make a prediction, change a variable, run the experiment, and explain the result. Finish with a challenge that tests your understanding.
You can change: Speed. Compare what happens and connect the result to the scientific explanation.
Try a comparison in Orbits
Start with the lab’s initial settings. Choose one control below, predict the result, and change that control while keeping the others fixed. Record the setting and what you observe before making a second change.
- Speed: the lab starts at 1; its available range is 0.45–1.7.
For a named starting condition, try Slow, Path, Fast. A preset can change several settings: check the controls before treating two presets as a one-variable comparison.
Questions to discuss during the activity
- Watch what happens. It is always falling toward the sun, and always missing. Watch a world hold its path.
- Name the cause. Gravity pulls inward. Sideways speed carries it past. Too little sideways speed, the pull wins and it falls in. Too much, it climbs away and leaves. Sideways speed is what saves it.
- Change something. Lower the speed and the path should fall inward. Change speed, then release.
- Guess before you run. If we drop the speed to 0.55, the world will… Guess what will happen, then run to check.
After your comparison, explain how the observations connect to this idea: Too slow, it falls in. Too fast, it leaves. The right speed is a fall that never finishes — an orbit. Name one condition you held fixed and one feature of the real world this model simplifies. A completed run is a starting point for discussion, rather than proof of mastery.
Who is it for?
Curious learners exploring physics. A parent or teacher can help younger learners read the instructions and discuss the results. Choose by topic and prior knowledge rather than a fixed grade level.
Is this lab free?
Yes. This interactive lab is free without signing in or a paid membership.
No app download is needed; interactive play requires JavaScript and a modern browser.
Use this activity with a learner
Families and educators · choose by prior knowledge
Learning goal: Too slow, it falls in. Too fast, it leaves. The right speed is a fall that never finishes — an orbit.
Before you begin: Read the controls for Speed. Make one prediction before changing a setting.
Check understanding: Ask for one observation, the evidence that supports it, and a question to investigate next.
A simulation simplifies the real world. Explain which conditions stayed fixed; a successful run alone does not demonstrate mastery.
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Activity and guide by Lesson Worlds. About the platform.
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