Physics is not Fair

## Question:

When I read the examples in my physics mechanics book, I think I have a good idea of whats going on and the examples that are done in the book seem easy but when I go to do a problem I never seem to get the problems right. The only problems I get right are the first couple of easy ones. On my last test I thought I understood everything but when I came to take the test it was like I didnt understand a thing. I studied a whole weekend for the test and a couple of hours here and there before that weekend but I did horribly on the test. It just isnt fair. What is the problem?

## Answer:

I believe the root of your problem lies in the difference between knowledge and understanding. It is possible to follow an example in a textbook and come out knowing how it was done. That means that if you are faced with that same problem again you will be able to solve it, providing you have not forgotten how it went in the meantime. This is an example of knowledge. It requires you to remember equations like y=1/2*a*t^2+v0*t+y0 and apply it appropriately. Of course if the question is asked in a different way, you may have trouble recognizing that this is the correct formula to use.

If you understand that the above example formula follows from the fact that under constant acceleration the average velocity is just half the sum of the initial and final velocities, then you can work all constant acceleration problems without remembering any particular formula. This is an example of the power of understanding. It is much more efficient than knowledge since you do not have to learn a huge number of specific examples to be successful.

Now regarding fairness... You are perhaps correct. I might consider it unfair that I can not play basketball like Michael Jordan did or do physics like Albert Einstein did. All we can do is the best we can with what we have. It is possible to compensate for some deficiencies in talent with hard work but the problem is that those talented people work just as hard as we do. If you can take the time to dig into physics until you really understand, you will do much better. There is likely to be someone in your class though for whom that understanding comes as naturally as breathing. Perhaps you are such a person and only needed someone to point out that understanding is different than knowledge to get you started.