Forces & Motion
📋 What it is
A force is a push or pull; an unbalanced force changes how something moves.
🗣️ Coach says
Nothing speeds up, slows down, or turns without a force — a push or a pull. When forces balance, motion stays the same; when one wins (unbalanced), motion changes. Gravity, friction, and your muscles are all forces you use every day.
🧠 Memory hook
Force = push or pull. Balanced = no change; unbalanced = motion changes.
😂 Giggle
Why did the apprentice Smith bring a ladder to the lab?
She heard the experiment had high stakes!
😲 Whoa!
In frictionless space, one gentle push would send an object gliding forever — motion stops here only because friction fights it.
✅ Quick check: A ball rolls and slowly stops on grass. What force stopped it?
Say your answer out loud first — then reveal.
Friction — an unbalanced force acting against the motion, slowing it until it stops.
Friction opposes motion and, being unbalanced, changes the ball’s speed.
🧪 Try it! (2 minutes)
Roll a ball on carpet, then on a smooth floor. It travels farther on smooth — less friction.