physics notes

1. For liquid at rest, the pressure at a certain point in the liquid is the same in all directions.

2. The pressure in a liquid is due to

a) Density of the liquid, p.
b) Depth of the liquid, h below the surface liquid.
c) Acceleration of the gravity,g.

3. The pressure on a liquid is proportional to the density of the liquid, p and the depth, h, at which the liquid is measured.

4. The pressure in a liquid at rest (static liquid) is independent of the shape (area and slope)o
of the container.

5. The applications of pressure in liquids are:
i) Dams
ii) Domestic Water supplies

i) Dams

- Dam is very much thicker at the bottom than at the top, since the pressure at the bottom is the greatest.

- Large dams are built for the hydroelectric generation of electricity.

- The high pressure on the deep-water side of the dam causes water to flow through these holes at great speed turning the turbines in the holes and generate the electricity.

ii) Domestic Water Supplies

- The main water comes from a reservoir but in order to maintain a constant high pressure to the consumer, it is pumped to the top of a water tower located on high ground.

- The main pressure is determined by the height, h.