P2.3.4 - Pressure in Liquids Flashcards
1
Q
Why do objects float in water?
A
- There is a force on the bottle from the air molecules hitting it and the water molecules hitting it.
- There are more frequent collisions due to the water molecules than the air molecules.
- So there is a net force upwards which balances the weight and it floats.
2
Q
Describe what happens to water pressure the deeper you go under water.
A
Pressure increases the deeper you go.
Because there is a greater weight of particles on top.
If you double your depth under water, you will double the water pressure.
3
Q
What is water pressure?
A
Where water molecules collide with the surface of an object.
4
Q
Why does the wall of a dam need to be thicker at the bottom?
A
Because water pressure increases the deeper you go.
There is a greater weight of particles.
This stops the dam bursting.
5
Q
In which direction does water pressure act?
A
All directions
6
Q
Can water be compressed?
A
No because its particles are touching.
