Lesson 1.3 - Pressure Part 1 PDF

Lesson 1.3  While you sip the beverage, you’re actually applying ‘Pressure’.  As the air pressure inside the straw is reduced by sipping, the greater atmospheric pressure on the liquid's surface pushes the liquid up into the straw. Pressure  ph...

Lesson 1.3  While you sip the beverage, you’re actually applying ‘Pressure’.  As the air pressure inside the straw is reduced by sipping, the greater atmospheric pressure on the liquid's surface pushes the liquid up into the straw. Pressure  physical force exerted on an object  force applied is perpendicular to the surface of objects per unit area  Pressure (P) = Thrust/ Area  SI unit is ‘pascals (Pa)’. 1 Pa = 1N/m2  Example of Pressure in Real Life  While cutting fruit or a vegetable, a sharp knife is used instead of a blunt one so that the pressure applied on the fruit is more and the fruits cut easily.  Example of Pressure in Real Life  Porters put a round piece of cloth on their heads in order to increase the area and the pressure is less so that heavyweights can be applied. Example of Pressure in Real Life Pressure is directly proportional to force, and inversely proportional to area  Types of Pressure  Atmospheric Pressure  Absolute Pressure  Differential Pressure  Gauge Pressure Solution (1) Solution (1)  Solution (2) Force = weight of the block 40 x 10N = 400N Since P = F/A A=F/P = 400/20 = 20m^2  Pressure in Liquids  Water on any liquid exerts pressure on the side of the container and this pressure increases with increase in depth  Pressure increases with depth  Pressure and depth are directly proportional