Introduction

A profoundly simple method for solving physics problems. Or, why almost all advice about learning physics is wrong.

Introductory physics is dreaded for one main reason: it makes smart people feel stupid. But it really isn't any more difficult than the other sciences, it's just generally not taught well. Or more specifically, it's taught well enough to attract a handful of future physicists. But the overwhelming majority of students who take intro physics are not going to be physicists, so they need to be introduced to the concepts of physics in a more directed way.

In my experience teaching physics, students think that by the end of the course they have learned a lot, when in fact they've only learned a few things, but have had to apply what they've learned to many specific situations. Physics is difficult because applying general techniques to new and unfamiliar problems is difficult. You will be tested on your problem-solving skills, not your knowledge -- this is the fundamental difference between physics and the other sciences (at least at the introductory level). And this is precisely why many programs use physics to weed out the weaker students: you can't "study" your way through physics in the traditional sense. You absolutely have to roll up your sleeves and practice solving problems, many of which will frustrate you to the point of tears! Or at least, they will if you don't take the approach I outline here...

I want to convince you that in your first semester of introductory physics you will learn exactly three things:

1. Newton's 2nd Law
2. Conservation of linear and angular momentum
3. Conservation of energy

These three laws are all you will need to solve almost every problem you will encounter. Things get tricky when you have to apply these three simple laws to complicated physical systems, but it is imperative that you always keep these laws in mind as you approach each new problem.

In this blog I will provide solutions to standard physics problems, and will show how one should approach each problem with the three laws in mind.