Project: Design a Roller Coaster

Lesson 10 of 10 · 8 min · Free, no account needed

What you will learn

A coaster gets all its energy from the lift hill: mgh at the top. After that it only trades height for speed and loses some to heat.
Friction keeps taking energy all the way, so later hills must be lower. Tall hills go early.
To stay on a loop of radius R without friction the cart must start at least 2.5 R high.

Every coaster spends one hill's worth of energy. Design a ride that makes it home.
Draw a first draft from the lift hill to the station, then Ride.
The station is 5 m up. The ride loses 20% of its energy. How high must the first hill be?
Drag the marker, then Check.
Tune the lift hill so the cart gets home gently.
It must clear the 8 m hill and arrive at the station at no more than 9 m/s.
A cart drops 20 m without friction, starting at rest. How fast is it at the bottom, in m/s?
Build your coaster from four segments. At least two hills, and it must get home.
Tap a blue slot to change its piece. Check rides it.
Ride your coaster. Watch the energy bars and the g-force.
A friend's coaster rolls back at its second hill. Fix it.
Drag the orange hilltop down, then Check.
Challenge: Loop it. Find the lowest start that still gets the cart round the loop.
No friction here. Fewer launches, more stars.
Code: a game engine logged the total energy each frame. Tap the frame where the program made energy from nowhere.
Start at 10 m. Friction takes 1 m of height energy before the hilltop. Make the cart stop exactly on top.
Drag the hilltop, then Check.
Same hills, different order. Which track makes it home?
Tap a track, then Check: both ride.
Final run: your coaster. Press Play.

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