1. Forces
1.1. Magnetic force
1.1.1. Magnetic force is the force of attraction between two objects made of magnetic material
1.1.1.1. Each magnet has a North & South pole. Like poles repel & unlike poles attract
1.2. Tension force
1.3. Air resistance
1.3.1. Air resistance is the friction between an object & the air trying to move in the air. Any object that try to move through the air is met with air resistance
1.4. Applied forces
1.5. Electrical force
1.5.1. The force exerted due to motion of electrons in an object is called electrical force
1.6. Frictional force
1.6.1. Frictional force is produced when two surfaces move against each other
1.7. Gravitational force
1.7.1. Gravity or gravitational force is a force of attraction. It's like the Earth pulling on you and keeping you on the ground. That pull is gravity at work
1.8. Elastic force
1.9. Effects of Forces
1.9.1. Decrease the speed of a moving object
1.9.2. Increase the speed of a moving object
1.9.3. Change the direction of which an object is moving in
1.9.4. Change the shape of an object
1.9.5. Make a stationery object start moving
1.9.6. Make a stationery object stop moving
2. Pressure
2.1. DEFINITION: pressure is the force exerted per unit area. pressure increases when force increases or area decreases
2.2. Formula for calculating pressure: Force divided by weight
2.2.1. S1 unit for pressure: N/m2 (also known as pascal)
2.3. The larger the surface area of an object, the more pressure it exerts on another object
2.3.1. You can push a nail into wood but you cannot push your finger into the wood. That is because the surface area of the finger is larger than the nail. Thus with the nail, the amount of pressure is higher.
2.3.2. E.g A sharp knife exerts more pressure than a blunt knife