Create an animated lesson
On requestThis article is free to read. Creating a lesson uses your daily or stored credits; review the language and settings before starting.
What are Newton's laws of motion?
Quick answer
Newton's three laws of motion describe how objects move and respond to forces. Together they explain everything from a rolling ball to a launching rocket, and form the foundation of classical mechanics. First law (inertia): an object stays at rest or in steady motion unless a force acts on it.
Key things to understand
- First law (inertia): an object stays at rest or in steady motion unless a force acts on it.
- Second law: force equals mass times acceleration (F = ma) — heavier objects need more force to accelerate.
- Third law: for every action there is an equal and opposite reaction.
- They apply at everyday speeds and sizes; at extreme speeds or tiny scales, relativity and quantum mechanics take over.
People also ask
What is Newton's first law?
The law of inertia: an object won't change its motion unless a net force acts on it. A still object stays still; a moving one keeps moving at constant velocity.
What does F = ma mean?
The force on an object equals its mass times its acceleration — so the same force accelerates a light object more than a heavy one.
What's an example of the third law?
A rocket pushes gas downward (action), and the gas pushes the rocket upward (reaction), propelling it into the sky.
Part of the guide: Cars, Trains, Planes & Ships →