Cheatography

# Physics Term 1 Yr9 Cheat Sheet (DRAFT) by Lyn.M.M

Physics Year 9 IGCSE Term 1

This is a draft cheat sheet. It is a work in progress and is not finished yet.

### Speed and distance time graphs

 Speed: Interp­reting a distan­ce-time graph: to calculate speed we need to know the distance travelled and the time taken Distance time graphs show us the relati­onship between the distance travelled and the time taken to cover it. avg speed= total distance (m) ÷ total time (s) A straight flat line means the object is at rest beacause distance is not increasing and time is simply moving on. speed= distance ÷ time (s=d/t) A steeper slope would imply accele­ration if it is increasing and deacce­lar­ation if it is decreasing We can interpret a straight line as steady speed At any point in the graph you can find the speed by finding the slope as you would for any other graph

### Mass, Weight and Fields

 What is mass? what is weight? Mass is a measure of much matter there is in an object. Weight is a measure of the effect of gravity onan object. How to calculate mass: How to calculate weight: W=mg

### Gravit­ational field strength

 what is gravit­ational field strength? A gravit­ational field is a region where a mass experi­ences a force, gravit­ational field strength is a measure of the strength of that field gravit­ational field strength is measured in (N/Kg) newtons per Kg How to find gravit­ational field strength: Gravit­ational field strength is calculated using the formula g = GM/r², where G is the gravit­ational constant, M is the mass, and r is the distance.

### Straight line graphs

 what is the equation of a straight line graph? y=mx the equation linking weight mass and gravit­ational field strength is: W=mg , (weight= mass x gravit­ational field strength)