Energy Changes Form

Lesson 1 of 10 · 5 min · Free, no account needed

What you will learn

Energy is a store that things have. Height and motion are two of its forms.
Going down, height energy (potential) turns into motion energy (kinetic). Going up, it turns back.
Without friction the total stays the same, so a skater can climb back to her start height, never higher.

A skater drops in from the top of a half-pipe without pushing. How high can she get on the other side?
Drag the flag to your bet.
Press Play. Watch the two bars while she rides.
Violet is energy stored in height. Blue is energy of motion.
Drag her to a different height and let go. Do it three times.
Where does she turn back each time?
What you saw has names.
Energy is a store that an object has. It changes form, but here it never appears from nothing or vanishes.
Potential energy is energy stored by position, here by height. Kinetic energy is energy of motion.
An energy transfer moves energy from one store to another: height to motion on the way down, motion to height on the way up. Simplified model: no friction, no air, so the total stays fixed.
Game: Reach the flag. Shape the ramp so she touches every flag.
Three levels. Fewer tries, more stars.
Tap the spot where she moves fastest.
Your ramp against a ramp with the flag above the start. Press Play.

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