forces and pressure

1. what are forces

1.1. its a push or a pull

2. what are the effects of forces

2.1. 1. Change speed(faster slower) 2.change shape 3.change direction 4.stop a moving object 5.start a stationary object

3. how can we measure a force

3.1. Instuments to measure amomt of forcespring balance ,compression balance Unit of force:newton,N

4. important forces

4.1. frictional force

4.1.1. Occur when 2 moving surfaces are in contact . Effects:heat produced ,slow down moving object, causing wear and tear

4.2. magnetic force

4.2.1. Magnetic force Is a force exerted by a magnet on another magnetic materialsteelironnickelcobalt [n s] [n s ]repel [s n] [s n]attract Like poles repel unlike poles attract . Examples of magnetic force-maglev train

4.3. gravatitional force

4.3.1. a force that pulls an object to the earth (gravity) gravititional force =weight mass amount of matter in an object weightamount of force due to the earths gravititional pull Weight =mass gravatitional field strength (g earth =10 ms)

5. how do we measure pressure

5.1. Pressure : Definition:amount of force exerted per unit area Units:pascal,PA Formula:force /area High pressure: increase force, decrease area Sharp knife :great force it can produce a higher temperature as it has a small surface area . Just remember the formula hehehehehehe