Key Stage 3
Meaning
Upthrust is a force that acts upwards in a fluid due to the fluid being displaced.
About Upthrust
- The force of upthrust is equal to the weight of fluid that has been displaced.
- An object in the water experiences as lot of upthrust because water is dense.
- Upthrust is weak in the air because the air is not very dense. For most objects in air upthrust can be ignored because it is so small.
Examples
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| A boat floats on the water because the weight is balanced by the upthrust. | A submarine can change the amount of upthrust in order to rise or sink in the water. |