1. Pressure
1.1. What is pressure
1.1.1. Pressure is the amount of force acting on a surface area.
1.1.2. SI unit of pressure is: Pascal(Pa)
1.1.3. Pressure = force/area =N/M2
1.1.4. How to increase pressure
1.1.4.1. By increasing the force exerted
1.1.4.2. By decreasing the surface area in contact
1.1.5. How to decrease pressure
1.1.5.1. By decreasing the force exerted
1.1.5.2. By increasing the surface area in contact
2. Force
2.1. Measured in Newton
2.2. Measured by a spring balance
2.3. Types of forces
2.3.1. Friction
2.3.1.1. the force between two objects in movement
2.3.1.2. e.g. between a tyre and the road.
2.3.2. Gravity
2.3.2.1. 1N=1kg
2.3.2.2. A pulling force exerted by the earth on objects e.g. a ball dropping is caused by the earth's pull /gravity.
2.3.3. Magnetic
2.3.3.1. magnetic materials
2.3.3.1.1. Nickel
2.3.3.1.2. Zinc
2.3.3.1.3. Iron
2.3.3.1.4. Steel
2.4. Effects of force
2.4.1. Change the shape of an object
2.4.2. Change the state of an object
2.4.3. Change the direction of an object
2.4.4. Stop a moving object