Forces and pressure
by Farhana Gazzali
1. what is a force
1.1. a push or pull
2. effects of force
2.1. change shape/size of a object
2.2. change speed of moving object
2.2.1. New node
3. Measuring force?
3.1. spring balance
3.1.1. extention spring balance
3.1.1.1. compression spring balance
4. Important forces?
4.1. Frictional force
4.1.1. occurs whenever two moving objects in contact
4.1.2. slows down a moving object
4.1.3. produces heat/ wears away materials
4.1.4. helps us to run/walk/hold things
4.2. Magnetic force
4.2.1. magnets exert a force called magnetic force
4.2.1.1. attraction/repulsion
4.2.2. maglev trains make use of repulsion from magnets to move
4.3. Gravitational force
4.3.1. a force that pulls objects towards the earth
4.3.2. gravity depends on weight of object an
5. What is a pressure
5.1. depends on force and area
5.2. higher pressure=more force, less area
5.2.1. New node
5.3. lower pressure= less force, more area
6. Calculating pressure
6.1. Pressure= Force/Area
6.2. SI unit= pa ( 1pa=1N/m2)
6.3. Example: If a elephant weighs 40 000 N. Stands on one foot with area 1000cm3.
6.3.1. Answer: 40 000 N (force)/ 1000cm3(area= 40N/cm3
7. Lower Pressure
7.1. skiing
7.1.1. Camel