## Fear and Physics

(from mozzercork on flickr)

If you have a tough physics problem, you might hesitate to even start it.

Use lots of paper and just write down what comes to your mind.

It might be completely wrong, but it doesn’t matter, you’ll find out pretty quickly by doing simple checks (dimensional analysis, feasibility, etc)

Thomas Edison tried 10,000 materials for filaments before getting the electric light to work.

And complex physics problems can get somewhat ridiculous.

If you start a problem earlier, it will be in the back of your head.

Professor Barber even told us that he has gone to sleep and woken up with the answer.

## Dimensional Analysis in Physics – Checking Answers

Dimensional analysis

Dimensional analysis allows a quick check of your answer by seeing if the units are correct.

An example would be if you are finding a distance by multiplying a speed by a time.  The units of distance are meters and the dimensional analysis of the product is [velocity*time] = [(m/s)(s)] = [m]

Google can do this automatically (with SI units) for an even faster check.