Force and Pressure

1. depends on 2 things

1.1. force

1.2. area

2. Pressure increases when the force increases or when the area decreases

3. not the same as force

4. pressure is the force acting per unit area

5. Forces

5.1. Main types of forces:

5.2. Frictional Force

5.2.1. Occurs whenever two moving surfaces are in contact

5.2.2. Slows down an object

5.2.3. Stops a moving object

5.2.4. Can be useful or not useful to us

5.2.5. Ways to reduce:

5.2.5.1. using smooth surfaces

5.2.5.2. ball bearings

5.2.5.3. lubrication

5.2.5.4. streamlined body shape

5.3. Magnetic Force

5.3.1. like poles repel

5.3.2. unlike poles attract

5.4. Gravitational Force

5.4.1. a force that pulls the object towards the earth

5.4.2. exists between any 2 objects

5.5. SI Unit : Newton (N)

5.6. Instuments used to measure force

5.6.1. extension spring balance

5.6.2. compression spring balance

6. calculating pressure

6.1. SI Unit : N per metre sq OR Pascal (pa)

6.2. Pressure = Force/Area

7. Pressure

7.1. increasing presure

7.1.1. when a smaller surface is in contact with an object, the pressure exerted on the object is higher

7.2. reducing pressure

7.2.1. when a larger surface is in contact with an object, the pressure exerted on the object is lower