Physics · Chapter 5: Mass, weight, friction and pressure
Year 11 Science · About 17 minutes with activities · Turn your sound on
Chapter 5 recap
- Mass is the amount of matter (kg) and never changes. Weight is a force (N): Fw = mg, g = 9.8 m s⁻² on Earth (smaller g on Mars → less weight).
- Friction opposes motion or attempted motion. In free fall, weight stays the same while air resistance grows with speed until they balance: terminal velocity (none in a vacuum).
- Pressure = force over area: P = F/A in Pa (N m⁻²). Smaller area → bigger pressure. Two shoes → total area = 2 × one shoe.
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