Physics A-Level
Upthrust
What Upthrust means in Physics A-Level, as defined for AQA, OCR.
Definitions of Upthrust
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Reference: OCR
A force acting upwards through the fluid, which together with drag balances weight at terminal velocity.
The weight of displaced air, which can be expressed using the air density and the droplet volume.
The upward force exerted by a fluid on an object immersed in it, due to pressure differences.
Topics that use Upthrust
- Principle of Millikan’s determination of the electronic charge, e (A-level only) (AQA A-Level)
- Dynamics (OCR A-Level)
Related terms
- Combining gravitational, viscous and electric forces
- Drag
- Drag in gases
- Electric force on a charge
- Electric force on a charged droplet in a uniform field
- Elementary charge
- Equilibrium of forces
- Free fall with drag
Using Upthrust in the exam
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