InquilineKea wrote:So I know that there have to be some not-too-easy problems on the Physics GRE, in order to create the curve. But on the other hand, the problems must be short. The shortness of the problems will automatically eliminate textbook problems that demand proofs and long answers.

From my experience, it seems that test questions are almost always easier than homework questions. People will always manage to get some of the problems wrong, even when most of them are easy (this was what I observed in AP and SAT II tests, where even strong students could get significant numbers of easy problems wrong - the problems would be very easy if they were assigned as homework problems in class instead).

So when you review for the Physics GRE, do you just aim for the easy/short problems on textbooks? Especially if you're crunched for time? Ideally, going for the longer/harder problems would help with understanding (and intermediate steps), but I wonder how useful those really are for the Physics GRE.

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Also, is magnetic potential important to know?

As you have pointed out, the test can't check your ability to derive formulas or solve elaborate problems and the problems on the PGRE have been created with that in mind. As such, nearly all of the problems can be solved simply by reasoning away answers from the multiple choices based on your knowledge of the physics in the problem. The hope of the universities you are applying to is that a good grade on the test will indicate a person who has good intuitions and good logical reasoning skills for physics topics.

As an example, one of the tests (I think it is 9677) has a question about the net current in a circuit when a potential has been allowed to charge a capacitor in the circuit. The connection is then broken from the potential and you have to figure out which plot on a current v time graph would match the situation. Because there is a resistor in the circuit and since you should know that Ohm's law tells you I=V/R, the curve should decrease with an inverse shaped line. Just knowing this allows you to eliminate all the answers except two, at which point you simply use one last piece of information to get the final answer (or at the very least you guess with a 1:2 chance of getting it right).