Algebra Is Like Sunscreen

Every year around this time, references to that damn sunscreen speech pop up again, as people start thinking of graduations. It’s in the air (Union’s graduation is this Sunday, and I don’t think I’ve ever been happier to see the end of an academic year).

And, of course, I have actually been asked to give a graduation speech. Which leads naturally to thinking about what one piece of advice I would give to a high school student who came up to me and said “I plan to study physics in college. What one thing should I study?”

(Hey, it could happen…)

My one-word piece of advice for students planning to study physics (or any other science, really, but mostly physics): Algebra.

If you have the slightest interest in physics, learn to do algebra. Learn it backwards, forwards, upside-down, and sideways. Get comfortable with x and y, and all the other variables.

Make up equations and solve them. Practice solving systems of two equations for two unknown quantities. Generalize that to N equations with N unknowns. Find unknown quantities in terms of other abstract symbols.

Solve quadratic equations, factor polynomials, learn to manipulate trig functions and logarithms. If you’re feeling really ambitious, play around with complex algebra– let i be the square root of -1, and go to town.

“What about calculus?” you ask. “Isn’t physics all about calculus?”

Yeah, there’s plenty of calculus in physics. But calculus, we can teach you in college. It does you no good to know how to take a derivative if you don’t know how to do algebra once you’ve got the answer.

The top-of-the-list, number-one-with-a-bullet way that students go wrong in introductory physics is by failing to do algebra correctly. If there’s one thing you need to know going into college, algebra is that thing.

Sunscreen is overrated. Stay in the shade, and learn to do algebra.