Thermal physics
Gas laws
EquationP₁V₁ = P₂V₂constant T, n
Compression (constant T)
P–V graph
Hyperbolic isotherm. Yellow dot = current state.
Real world
- 🤿Scuba — gas in lungs expands as diver ascends.
- 🩺Breathing — diaphragm lowers volume to draw air in.
- 💉Syringes — reduced pressure draws in fluid.
Curriculum
WAECNECOIGCSESATJUPEB
📋 Teacher notes
- •Boyle's Law: at constant T, pressure and volume are inversely proportional — P₁V₁ = P₂V₂.
- •The P–V graph is a hyperbola. Each curve (isotherm) represents a different temperature.
- •Higher temperature isotherms sit above lower ones — more energy means higher pressure at same volume.
- •Real gases deviate from this at very high pressures or near condensation.
- •Ask: what happens to particles when volume decreases? Why does pressure increase?
✏️ Exercises