Don’t Be Scared, It’s Only Physics

Many people are a little on edge when they think about physics. It’s easy to feel

intimidated by the subject, thinking it seems like some foreign high-brow topic

that pulls numbers and rules out of thin air. But the truth is that physics exists

to help you make sense of the world. It’s a human adventure, undertaken on

behalf of everyone, into the way the world works.

Although the contrary may seem true, there’s no real mystery about the

goals and techniques of physics; physics is simply about modeling the world.

The whole idea behind it is to create mental models to describe how the

world works: how blocks slide down ramps, how stars form and shine, how

black holes trap light so it can’t escape, what happens when cars collide, and

so on. When these models are first created, they often have little to do with

numbers; they just cover the gist of the situation. For example, a star is made

up of this layer and then that layer, and as a result, this reaction takes place,

followed by that one. And — pow — you have a star.

As time goes on, those models start getting numeric, which is where physics

students sometimes start having problems. Physics class would be a cinch if

you could simply say, “That cart is going to roll down that hill, and as it gets

toward the bottom, it’s going to roll faster and faster.” But the story is more

involved than that — not only can you say that the cart is going to go faster,

but in exerting your mastery over the physical world, you can also say how

much faster it will go.

The gist of physics is this: You start by making an observation, you create

a model to simulate that situation, and then you add some math to fill it

out — and voilà! You have the power to predict what will happen in the

real world. All this math exists to help you feel more at home in the physical

world and to help you see what happens and why, not to alienate you from

your surroundings.

-Physics for Dummies book by: Steven Holzner, PhD-