AP Physics 2 / Unit 9: Thermodynamics
9.1 Kinetic Theory of Temperature and Pressure
Notes
Temperature measures the average kinetic energy of particles: $\displaystyle K_{avg}=\frac{3}{2}k_BT$.
- Gas pressure comes from particles colliding with container walls.
- At the same temperature, lighter particles move faster.
Practice
Doubling the kelvin temperature of a gas doubles its:
$K\propto T$.
Gas pressure is caused by:
Momentum transfer.
At the same temperature, helium atoms compared with oxygen molecules move:
Same KE, smaller mass.
Ready for more? Take the Unit 9 test.