Mistake Master
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Mistake Master · AP Physics 1 · Unit 3 · Step-Through Animation

Every Joule, Accounted For

You'll learnthat energy only changes columns, so the total never moves.

One ball, one hill, and a ledger that refuses to lie. Watch kinetic, potential, and thermal energy trade places on a live bar chart — and see why the total column never, ever moves.

8 STEPS · 6 QUICK CHECKS · g = 10 m/s² · v5

ENERGY LAB
Before you start
What you're looking at
A 1 kg ball at rest atop a 5 m hill, beside a live bar chart holding kinetic, gravitational, thermal, and a total column.
The question
As the ball rolls down, can the outlined total bar ever move, frictionless world or rough one?
Watch for
Kinetic and potential trading places joule for joule on the way down; predict whether the outlined total stays fixed.
What the symbols mean
K is kinetic (blue), Ug gravitational potential (amber), Eth thermal; the outlined bar is the total, all in joules.
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