Position, Velocity and Acceleration
Lesson notes
Overview
Three linked graphs: velocity is the slope of position and acceleration is the slope of velocity. This topic is rated beginner and is number 1 of 227 in Physics. Core ideas and first intuitions. No prior knowledge needed.
What you are seeing
The panel above shows an interactive animation of the idea. Every slider changes one quantity so you can see its effect on the outcome. The animation is drawn live from the model, so everything you see responds to the sliders. Press Space to pause, use Restart to replay from the start, and change the speed to slow down quick events.
In depth
These three quantities describe motion and are linked by calculus. Velocity is the rate of change of position, the slope of the position–time graph, and acceleration is the rate of change of velocity, the slope of the velocity graph. Going the other way, the area under an acceleration graph gives the change in velocity, and the area under a velocity graph gives the displacement. Reading all three graphs together tells you whether an object is speeding up, slowing down or turning around.
Reading the relationship
The expression "v = dx/dt, a = dv/dt" is a compact summary of the idea. It uses the symbols v, d, x, t, a; name what each one stands for before you start. Notice that it contains a ratio, so increasing the denominator makes the result smaller. Then use the sliders to see how changing one quantity changes the others.
A guided exploration
1. Run the animation once with the default settings and describe in words what happens. 2. Change one slider at a time and note which quantity responds most. 3. Push each slider to its extreme and decide whether the result still makes sense.
Try this
Start by only moving one slider at a time. Say aloud what you expect, then check.
Common pitfalls
Check units and directions first. Many mistakes come from mixing up a scalar with a vector, or from using a formula outside the conditions where it holds.
How it connects
Once you are comfortable, continue with “Constant Velocity (Inertia)”.
Why it matters
Physics explains how the world moves, heats, shines and interacts, and the same principles power technology around you.
Where you might use it
- Revising “Position, Velocity and Acceleration” before a class, exam or certification
- Designing vehicles, bridges and devices where motion, forces or waves must be predicted
- Understanding how sensors, lasers and communication links actually work
- Explaining everyday phenomena such as sound, light, heat and orbits
Frequently asked questions
What is Position, Velocity and Acceleration?
Three linked graphs: velocity is the slope of position and acceleration is the slope of velocity. It is a beginner topic in Physics.
How do I use the Position, Velocity and Acceleration simulation?
The panel at the top shows an interactive animation of the idea. Every slider changes one quantity so you can see its effect on the outcome. Move the sliders one at a time, then press Space to pause the animation and look closer.
What does the formula mean?
The expression v = dx/dt, a = dv/dt packs the idea into symbols. Name each symbol first, then change one quantity with the sliders and see which others respond.
Who is this topic for?
Core ideas and first intuitions. No prior knowledge needed. If the quiz feels hard, reread the lesson notes and try the previous topic first.
What should I learn before this?
Start with “Surface Tension and Capillary Rise”, the previous topic in Physics. Each topic in a subject builds on the ones before it.
How do I track my progress?
Press “Mark as learned” on this page. Progress is stored only in this browser and is never sent anywhere. The Browse page can show topics you have learned or still need to learn.
Quick quiz
More in Physics
See all →Constant Velocity (Inertia)
With zero acceleration an object keeps moving at constant speed in a straight line.
Uniformly Accelerated Motion
Constant acceleration gives a straight velocity graph and a parabolic position graph.
Free Fall
Without air resistance every object falls with the same acceleration g ≈ 9.8 m/s².