Class vii physics - pressure

Physics - Pressure

1. Pressure Chapter 13

2. Force and Pressure are NOT the same thing Force  is the total impact of one object on another.  Pressure  is the amount of  force  acting on an area.

3. Pressure Describes how a force is spread over an area It is a measure of how much force is acting on a certain area.

4. Pressure depends on 2 factors Forces acting – Increasing the force will increase the Pressure. Area of surface – Decreasing the area of the force will increase the Pressure.

5. Pressure in Liquids

6. Pressure in Liquids Pressure is transmitted throughout the liquid. Pressure acts in all direction. Pressure increases with depth.

7. Pressure in Liquids

8. Pressure increases with depth

9. Pressure in Liquid Formula

10. Hydraulic Machines

11. Things to remember: Pressure in a liquid is transmitted equally and throughout the liquid.

12. Atmospheric Pressure or Gas Pressure

13. Gas pressure increases when:

14. Measuring Instrument

15. Mercury Barometer Atmospheric pressure can be measured with a mercury barometer. The column of mercury is held up by air pressure. As the air pressure varies from day to day the height of the mercury also varies.

16. The distance to measure is shown in the diagram. A height of 760mm is called Standard Atmospheric Pressure.

17. Manometer