Momentum Carts
Class 9 Science: force and laws of motion (momentum)
Crash one cart into another. Make them bounce or stick together, change the masses and see that the total momentum never changes.
Words to know
- Momentum
- Mass × velocity. Unit: kg m/s.
- Conservation of momentum
- In a collision, the total momentum before equals the total momentum after (if no outside force acts).
- Collision
- When two bodies hit each other and push on each other for a short time.
- Velocity
- Speed in a given direction. Going left counts as negative here.
- Third law of motion
- When A pushes B, B pushes A back with an equal and opposite force.
Quick check
Answer 3 questions to check what you learned.
Try at home
Line up coins on a smooth table touching each other. Flick one coin into the row. Which coin moves off? Try flicking two coins together.