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Newton's laws of motion

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A bouncing ball captured in multiple positions to show how it moves and changes shape during each bounce, demonstrating physics concepts like energy and gravity.

Newton's Laws of Motion

Newton's laws of motion are three simple rules that help us understand how things move. These rules were first described by a scientist named Isaac Newton a long time ago. They help us figure out why objects stay still, speed up, slow down, or change direction.

The First Law: Staying Still or Moving Steady

The first law says that an object will keep doing what it's doing—either staying still or moving at a steady speed in a straight line—unless something pushes or pulls on it. This idea is called inertia. For example, when you slide a toy on the floor, it keeps moving until friction or something else stops it.

The Second Law: Force, Mass, and Acceleration

The second law tells us that the force acting on an object equals its mass times its acceleration. This means that if you push something harder, it will speed up more. Also, bigger things (with more mass) are harder to speed up. For instance, when you push a toy car, the harder you push, the faster it goes.

The Third Law: Action and Reaction

The third law states that for every action, there is an equal and opposite reaction. This means when two objects push each other, they feel the same amount of force but in opposite directions. For example, when you push on a wall, the wall pushes back on you with the same force.

These three laws help us understand many everyday things, from falling apples to cars moving on the road. Even though there are newer theories for very special situations, Newton's laws work very well for most things we see and do.

Images

Portrait of Emmy Noether, a famous female mathematician and scientist from the early 1900s.
The space shuttle Atlantis launches into space from Kennedy Space Center on its mission to the International Space Station.
A view of the Skylab Orbital Workshop floating in space, showing the space station with its solar panels and protective shield.
An illustration showing Newton's Sailboat, demonstrating the principles of motion and force.
Illustration showing the concept of equilibrium and center of gravity in physics.
An animation showing how tiny changes can cause very different motions in double pendulums, illustrating the concept of chaos in science.
Diagram showing how electrons move in a circular path inside a vacuum tube, creating visible glowing paths when they strike air molecules.
Portrait of Sir Isaac Newton, a famous scientist from the 17th century.
First edition of Sir Isaac Newton's 'Principia Mathematica,' featuring his handwritten corrections for the second edition.
Animation showing how two objects orbit around their common center of mass in space.
Animation showing how a mass attached to a spring moves back and forth in a steady rhythm, demonstrating a basic physics principle.
Animation showing the complex movement paths of three objects with the same mass interacting with each other through gravity.
An animation showing how tiny particles move randomly when bumped by gas molecules – a great example of Brownian motion!

Related articles

Motion
Isaac Newton
Inertia
Mass
Acceleration

This article is a child-friendly adaptation of the Wikipedia article on Newton's laws of motion, available under CC BY-SA 4.0.

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