Science
What is Newton's laws of motion?
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.
See it, don’t just read it.
Watch a 2-minute lesson with voice + animation that explains newton's laws of motion.
Key things to understand
- 1First law (inertia): an object stays at rest or in steady motion unless a force acts on it.
- 2Second law: force equals mass times acceleration (F = ma) — heavier objects need more force to accelerate.
- 3Third law: for every action there is an equal and opposite reaction.
- 4They apply at everyday speeds and sizes; at extreme speeds or tiny scales, relativity and quantum mechanics take over.
Frequently asked questions
- 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.