1. Force makes a moving object stop moving.
2. Force is an ability to do work.
3. We use a spring balance and a compression balance to measure force.
4. The pressure on the surface will increase if you make the force on an area bigger.
4.1. The ski board is long so it has larger exposed surface area, increasing the amount of pressure.
5. The pressure exerted by a given force can be decreased by increasing the area of contact.
6. Making the area smaller and keeping the force the same also increase the pressure.
7. Pressure is an expression of force exerted on a surface per unit area.
8. example of pressure: Stepping the foot with high heels
9. Force is a push or pull.
10. A force changes shape and size.
11. Force makes a stationary object move.
12. Force changes the direction of a moving object.
13. Force makes the world go round and without force we would fall of things because force pushes or pulls us back.
13.1. Example: When we sit on a chair, we need force to push us and hold us so we won't fall.
14. Types of force
14.1. Frictional Force
14.2. Normal Force
14.3. Air Resistance Force
14.4. Applied Force
14.5. Spring Force
14.6. Gravitational Force
14.7. Electric Force
14.8. Magnetic Force
15. SL Unit: Pascal
16. Formula: N/m2
17. Force
17.1. Force is a push or pull
17.2. Force's SL Unit is Newton (N)
17.3. Force can change size,change shape of object, move a stationary object, change the direction and also change the speed of an object.
17.4. Instrument to measure forces are the spring balance and compression balance
17.5. 3 Types of forces
17.5.1. Magnetic force
17.5.1.1. Magnetic force is a force exerted by a magnet on another magnet or on a magnetic material such as iron, steel, cobalt and nickel.
17.5.1.2. Unlike poles will attract while like poles repel each other.
17.5.1.3. We use magnetic force at the door of fridge, EZ Link, junk yard, magnetic door catch and magnetic train.
17.5.2. Gravitational force
17.5.2.1. Gravitational force (weight) is a force that causes objects to be attracted to the Earth due to gravity.
17.5.2.2. Examples of gravitational force are a coconut falling from tree and a ball being thrown up will come down.
17.5.3. Frictional force
17.5.3.1. To reduce friction, we need to use lubricants, ball bearing, or we smooth the surfaces by polishing the surface.
17.5.3.2. Friction also causes wear and tear and produces heat which is bad for an efficiency of the machine.
17.5.3.3. Friction enables us to walk and light matchstick
17.5.3.4. Friction slows down or stop moving things and produces heat.
17.5.3.5. Frictional force occurs when 2 moving surfaces are in contact
18. Pressure
18.1. Pressure is an amount of force exerted per unit area.
18.2. The SL Unit is Pascal which is also written as Pa.
18.3. The formula to calculate pressure
18.3.1. force/area
18.4. To increase pressure
18.4.1. increase force
18.4.2. decrease area
18.4.3. Examples
18.4.3.1. high heels
18.4.3.2. Sharp knife
18.4.3.2.1. It has a smaller surface area, so when we use the same force to cut something, a higher pressure will allow us to cut it easily.
18.5. To decrease pressure
18.5.1. increase area
18.5.2. decrease force
18.5.3. Examples
18.5.3.1. Army truck
18.5.3.2. Excavator
18.5.3.3. skiing
18.5.3.4. camel