CAPTER 10 PRESSURE

Basic Competency To describe pressure on solids, liquid and gases and also its application in daily life

Science word Pressure Force Area Fluids Archimedes principle Flooding Flying sinking Tekanan Gaya Luas Zat alir Hukum archimedes Mengapung Melayang Tenggelam

Diagram concept

After this you are able to : Describe relation between pressure and area Describe relation between pressure and force Write down formula of pressure

Pressure in solid Pressure is defined as force acting on unit area If pressure (p), force (F), and area (A), we can write the formula below

Pressure in solid The SI Unit of pressure is N/m2 or Pascal (Pa) The another unit such as Cm Hg, atmosfera (atm), Bar, dyne/cm2

Fluids How can a fluid produce pressure? Pressure in fluid is produced by collisions between particles and the container.

After this you are able to Describe the quantities that have effect to pressure in liquid Describe the characteristics of liquid pressure Write down formula of hydrostatics pressure

Pressure in Liquid What do you feel when you dive into water? Why did the engineer make dam have shape greater bottom?

The characteristics of liquid pressure Pressure in liquid increase with depth Pressure at one depth equally in all direction A liquid finds its own level in a U - tube Pressure depend on the density of liquid.

Formula of liquid pressure For the information above, pressure of liquid just depend on 2 variable : Depth (h), that have relation pressure ~ depth Density () that have relations pressure ~ density

Formula of liquid pressure We can write formula : p ~ .h or p = .g.h which pressure (p), depth (h), density ( ), and gravitation (g)

Example Alcohol has a density of 0.9 g/cm3. Water has a density of 1 g/cm3. At a depth of 40 cm which will have the greater pressure if they are both in open container ? Calculate the pressure of liquid above. water alcohol 40 cm

Pascal’s principle After this the student is able to state Pascal’s Principle applied Pascal’s Principle in daily life

Pascal’s principle Pressure applied to an enclosed liquid is transmitted to every part of liquid, whatever the shape of liquid.

Aplication pascal’s principle Pascal’s principle is applied in the operation of machines that use fluids to multiply force as in hydraulic lift

Hydraulic system In a hydraulic system fluid is confined in two connecting chambers. Each chambers has a piston that is free to move.

Pressure is transmitted throughout the fluid without change

Example A 50 newton force is exerted on the small piston a hydraulic system. The cross-sectional area of small piston is 0,05 m2. What is the magnitude of the weight that can be lifted by the large piston, which has a surface area of 0,2 m2?

Archimedes Principle

Archimedes Principle

Archimedes Principle

What do you fell if you bring something in the water? ???????? What do you fell if you bring something in the water? Why do it happen?