A-LIGNing Perspectives: Newton’s Laws

You may have heard a story about a man who sat under a tree and was struck by an apple that had fallen from it, causing him to ponder what causes gravity and subsequently arrive at a theory. While some details of this story may be inaccurate, this man did ideate the theory of “universal gravitation” and discover crucial laws of physics that reign true throughout our entire universe. His name was Sir Isaac Newton, an Englishman from the mid-1600s. Newton’s knowledge spanned from mathematics and physics to theology and literature, making him a prominent figure in both the Scientific Revolution as well as the Enlightenment.

Besides his laws of gravity, Newton is most famous for his three laws of motion. The first law states:

"An object at rest stays at rest, and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force."

This fact known as the Law of Inertia sounds simple and almost silly at first, as one may attribute it to common sense: things won’t move unless you move them… duh? However, it’s a fact that many people ignore in their day-to-day lives. Things don’t happen unless you make them happen. For example, if you want to learn a new skill, like playing an instrument or coding, you have to start practicing—nothing will change or improve unless you take the first step. As the LOI states, this logic applies in reverse as well. Things won’t stop happening unless they are stopped by something. If you’re caught in a toxic relationship, unless you actively end it or make a change, the negative cycle will continue on its own momentum. Just as objects do, your emotions, your relationships, and the events of your life have inertia; a force is required to change their trajectory. Newton’s second law states:

"The force acting on an object is equal to the mass of that object times its acceleration."

This law is most commonly expressed as a mathematical formula, but better understood through life experiences. Imagine you're pushing a shopping cart. If the cart is empty, it's easy to push and it moves quickly. But if the cart is full of groceries, it's much harder to push, and it moves slower even if you're using the same amount of force. You may also imagine trying to learn a new skill, like playing an instrument. If you are learning to play “Happy Birthday”, it may take a small amount of effort. But learning to play “Bohemian Rhapsody” with that same small effort will make your progress very slow. The second law uses “mass” and “acceleration”, but as you can see, it translates to everything from “groceries” and “pushing speed”, to “difficulty” and “pace of learning”. The third and final law of motion goes as follows:

“For every action, there is an equal and opposite reaction.”

A simple comparison would be a dispute between two retaliatory people. A conversation could be calm and orderly, but when person 1 begins raising their voice, person 2 raises theirs right back. When person 1 throws an insult, person 2 returns the favor. The same applies in a more positive context as well: after someone does a favor for you, you’ll likely feel inclined to return it. Newton’s third law can be seen as physics’ version of karma, a restatement of “treat others as you’d like to be treated”.

In physics, most if not all concepts connect to each other in some way, shape, or form. Therefore, the third law applies to much more than relationships. We can use the same analogy that we used to align the second law: the effort you spend to learn a skill. As the second law implies, the things you say or do to someone will affect them in different ways, depending on their character. A more sensitive person (a smaller mass) would react (accelerate) more to a sarcastic jab (force) than would a person with a more nonchalant attitude.

When considered outside of their common use in physics, the laws of motion become malleable enough to apply to our everyday lives. More specifically, the effects of our decisions, our words, and events can all be simplified by comparing them to forces.