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.

7. 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.

8. Pressure in Liquids

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

10. Pressure in Liquids

12. Pressure increases with depth

14. Pressure in Liquid Formula

16. Hydraulic Machines

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

22. Atmospheric Pressure
or Gas Pressure

26. Gas pressure increases when:

28. Measuring Instrument

29. 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.

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

32. Manometer