Mechanics · Kinematics
Chapter 1 · 3
The idea
Vertical motion under gravity
Why an object moving freely under gravity is just a constant-acceleration problem with a = ±g, how to choose a positive direction and translate "thrown up", "returns", "hits the ground" into suvat values, and why the up-and-down trip makes distance and displacement differ.
A full journey — read it, play with it, work it, then earn real exam marks. Everything stays on the timeline below.
In this lesson — start anywhere
Mechanics · Kinematics
Vertical motion under gravity
Why an object moving freely under gravity is just a constant-acceleration problem with a = ±g, how to choose a positive direction and translate "thrown up", "returns", "hits the ground" into suvat values, and why the up-and-down trip makes distance and displacement differ.
Why it works
Suvat with a = ±g
"Moving freely under gravity" is a modelling phrase with a precise meaning: the only force acting is gravity. That makes the acceleration constant — its size is (some questions tell you to use ), always directed downwards. Constant acceleration means the whole toolkit you already have applies: vertical motion under gravity is just suvat with . Nothing new — except discipline with signs.Keep reading — free
The rest of the explanation, plus 3 worked examples you step through move by move.
Start freeTakes a minute — no card.