Brownian motion
What Brownian motion means in Physics A-Level, as defined for AQA, OCR.
Definitions of Brownian motion
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Reference: AQA
The random, jerky movement of small particles such as smoke particles or pollen grains suspended in a fluid, seen as unpredictable zigzag paths under a microscope.
The random, jerky movement of small particles suspended in a fluid.
Topics that use Brownian motion
- Molecular kinetic theory model (A-level only) (AQA A-Level)
- Solid, liquid and gas (OCR A-Level)
Related terms
- Absolute zero
- Change of phase
- Collisions and resultant forces
- Conservation of momentum
- Constant temperature during phase change
- Elastic collision
- Empirical versus theoretical knowledge
- Energy transfer in melting and boiling
Using Brownian motion in the exam
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