This means that the rate an object is slowing down or speeding up (acceleration) depends on how hard it is hit, pushed, or pulled (force) and the mass of the object.

Let’s take a look at some examples to learn more about Newton’s Second Law. A truck hits a car; the car moves forward. The truck provides the force, the car is the mass, and the acceleration is how quickly the car (mass) moves forward. The larger and heavier the car (mass) is, the more force it takes to move it. If the car is very light, it will move forward quicker than if the car is very heavy.

If you throw a 10-lb. weight and a 2-lb. weight with the same amount of force, the 2 lb. weight will travel faster than the 10-lb. weight. That is because there is less mass to be moved.

Although few people could quote Newton’s Second Law, everyone has used it before. It is part of everyday life; the heavier something is, the harder you have to push to move it. You don’t really spend a lot of time thinking about it because your brain knows it so well. For example, if you think a door is heavy, your brain will automatically tell you to apply a lot of force, but if the door is actually light you will end up slamming it! Try this experiment to prove it. Take an empty, closed box and pretend it is really heavy. Tell someone to lift it for you. They will automatically apply a lot of force to lift it. Not only is it funny, you can see Newton’s Second Law in action!

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