Newton's Laws

Newton's 1st Law

Newton's 1st Law describes how an object in motion will stay in motion, or how an object at rest will stay at rest, until an outside force is applied.

The law is also sometimes known as the Law of Inertia. Inertia is the resistance an object has to a change in motion.

The golf ball in the picture was at rest, and would have stayed at rest, if not for the applied force of the golf club. This is one example of the first law in real life.

Another real life example would be riding a bike at a steady pace, and then pulling the break. The bike was in motion, until the force of the brakes were applied, causing the bike to slow or stop completely.

Newton's 2nd Law

Newton's 2nd Law says that the acceleration of an object depends upon the force, a push or a pull, acting on the object, and the object's mass, the amount of matter in an object.

Acceleration is the change in velocity of an object. The math formula to Newton's 2nd Law is F= m x a, or Force= mass x acceleration. If you didn't know what force an object had acting on it, you would multiply the object's mass with its acceleration to find the force.

In the picture, the wagon with the smaller mass will have a greater acceleration than the wagon with a larger mass. They're both being pulled by the same force, but because one has a greater mass, it's heavier and harder to move.

A real life example of Newton's 2nd Law would be pushing a car. You use your force to try to move the car's mass, to create acceleration.

Newton's 3rd Law

Newton's 3rd Law states that for every force, there is an equal and opposite force as well.

The picture depicts a person jumping on a trampoline, which is an example of the third law. When the girl lands back down onto the trampoline, it uses the same force that she landed with to launch her back into the air. If she decreases her force, so will the trampoline. If the girl increases her force, then the trampoline will also increase its force.

Another example of Newton's 3rd Law would be using a diving board. Like the trampoline, a diving board uses the force that a person puts on it by jumping, to launch them upwards and into the pool.