Ironically, I learned this from my high school chemistry teacher, who was a big stickler on units, but using them consistently and knowing them well will get you a long way in physics also.
- Always use units for at each point when plugging in values in the equation and as you calculate (add, multiple) numbers, you should also be doing that with the units.
- If you find you are adding two units that are not the same (i.e. m/s (a velocity) and m/s^2 (an acceleration), you know this is impossible and can look for a mistake you made (in this example, it is likely that the second term was missing a time variable – since multiplying by units for time, ‘s’, would give you velocity units)).
- When you multiply units, you might end up with a big fraction, but all units should cancel nicely to give you the units of whatever you find in the end. Here, it’ll help to know how “bigger” units break into “smaller” units (e.g. units for force, N = kg*m/s^2, this makes sense if you consider that F=m*a, the units for Newton are just the units for mass and acceleration multiplied).
Don’t let lots of information overwhelm you (like this webpage).
In physics, having lots of „knowns“ is a good thing! We might have to use more than one equation, but in a class, you can be sure you have everything you need!
- Follow the procedure outlined in the section below by making a list of things you know, including things we assume to be true, like gravity, and things you are asked to solve for – break things into x and y components at this step so that it makes it easier for you!
Realize that physics is about applying and less about memorizing.
I always had a rough time in life science classes because I am not good at memorizing lots of definitions, words, etc. – or maybe I just don’t want to. In any case, physics doesn’t ask you to memorize things – this is why the equations are given. You might memorize some of them down the line the more you use them – this is awesome – but you don’t need to! (Following the steps in the section below will help you choose the equation if you aren’t sure about which one.)
Eliminate easy and frequent errors.
As you go about solving problems, ask yourself questions, for example, did you consider negative signs for opposite directions? Doing more problems might tell you where you tend to make the same errors, like maybe you get sine and cosine confused.
Maintaining a positive attitude
Physics might seem a little weird, complicated, different, at the start, especially if this is your first class, but in the end it’s a very logical, albeit math-based (depends on if you like math or not) science.