Force and Pressure
by Ashley Tan
1. A force
1.1. A push or a pull.
1.2. A force cannot be seen but effects can be seen and felt.
2. Effects of a force
2.1. When we apply a force towards our body, it is a pull.
2.2. When we apply a force away from our body, it is a push.
2.3. A force can make an object move.
2.4. A force can make an object move faster.
2.5. A force can slow down or stop a moving object.
2.6. A force can make an object change the direction it is moving in.
2.7. A force can make an object change its shape.
2.8. Heat will be produced.
2.9. It can cause wear and tear.
3. How a force is measured.
3.1. A force can be measured using a spring balance.
3.2. It can be measured by multiplying the mass by the acceleration.
3.3. A force is measured in Newtons.
3.4. It can be measured using a compression balance.
4. Types of forces
4.1. Frictional force
4.1.1. It is the force resisting two surfaces against each other.
4.1.2. It can be reduced.
4.1.2.1. Putting lubricant
4.1.2.2. Ball bearings
4.1.2.3. Rollers
4.1.2.4. Polishing
4.1.2.5. Streamlining
4.2. Magnetic force
4.2.1. A magnetized piece comes close to either a magnet or another magnetized piece.
4.2.2. Like poles attract
4.2.3. Unlike poles repel
4.2.4. Examples that use magnetic force
4.2.4.1. Fridge door
4.2.4.2. Maglev train
4.2.4.3. Magnetic door catch
4.3. Gravitational force
5. What pressure is
5.1. Force per unit area applied to an object.
6. Reducing pressure
6.1. Increase the surface area of an object.
6.1.1. Examples of objects that reduce pressure.
6.1.1.1. Skiing
6.1.1.2. Camels
6.1.1.3. Army truck
7. Uses of high pressure
7.1. Sharp knife
7.1.1. Blade has small area, so with the same force, it can produce high pressure.
7.2. Spikes on soccer shoes
7.2.1. It must have high pressure so they will sink into the ground and have better grip.
8. Increasing pressure
8.1. Decrease the surface area of an object.
9. Calculating pressure
9.1. Formula for pressure
9.1.1. Pressure=Force/Area
9.2. Unit of pressure
9.2.1. pascal(Pa)