Nothing here gets created or destroyed — it just moves around, changes form, and sometimes leaks away as heat. This unit is about tracking where it goes.
The Path Through Unit 4
Release a pendulum from a measured height and track where its energy goes as it swings — how much stays kinetic, how much comes back as height, and where the rest quietly disappears.
Build a marble coaster out of foam tubing, then predict how high your marble can climb the next hill based on how much energy friction ate on the way there.
Design an emergency descent device — a slide, a chute, a controlled drop — that gets a rider to the bottom under a maximum safe exit speed, using a fixed materials budget. You decide the shape; the constraints decide whether it works.