# Physics

Ugghhh…Can I rant for a minute? Please? Is there a friendly cyber shoulder to cry on? I’m taking Physics I in this fall term, starting my journey towards med school and I’m trying soooo hard already. I’m reading the chapter, outling it and reading all the examples, get to the homework problems and: Argghh…Just when I think it starts making sense, they throw a curve ball at me that I can’t figure out.

This is soooooo frustrating. All this rearranging of equations, I just get tied up in circles.

This is so very discouraging when I’m trying so hard already (the term just started on Monday). Maybe I’m trying too hard, I dunno. But I’m trying, real hard and I get to a situation where I just draw a blank.

Maybe we could start a physics thread like the Chemistry thread on here where people can talk. I don’t know if it would help or not. The only real consoling thing for me right now is knowing that everyone out there who bears the title M.D. or D.O. has had to go through this same step in their journey to & from med school. So that gives me hope. Certainly I can’t be the only one who got confused in Physics.

Sigh…I’m going to bed. Been at it most of the day doing Physics & Chemistry. Still have Calculus to do tomorrow.

-Justin

Yep suffered through it this summer and have physics II this fall. Here’s my 2c. Hope it helps.

Physics is nothing but a very logical, step by step, application of a set of observations. Your formulae and equations are the observations and your problem is the application.

What helped me was to read the problem very slowly and at least 3 times. Then re-word the problem in your head, i.e., “We want to get from point A to point B in a circle at speed X, the static friction is Y, will the tires hold?”.

When you re-word the problem in your own statement then the next logical question in your head should be, “Ok, because we’re going in a circle centripetal acceleration is involved. The friction between the tires and the road is providing this centripetal acceleration. So I basically need to relate the centripetal acceleration to the static friction.”

As you’re talking to yourself, write down the equations for whatever you’re saying. DO NOT JUMP AHEAD BY TRYING TO DO THINGS IN YOUR HEAD TO SAVE TIME - WRITE EVERYTHING DOWN AND GO STEP BY STEP.

Then step back and look at the equations. You have your knowns and unknowns. Try to relate the equations with the unknowns on the left and knowns on the right. One major point - make sure you have as many equations as unknowns. If you have too many equations you may end up with more than one solution - look for redundancy and eliminate. If you have too few you may not arrive at a solution - DO NOT MAKE ANY ASSUMPTIONS NOT STATED IN THE PROBLEM.

If you run into a dead end while solving the problem, take a deep breath, and slowly re-read the problem. Usually you’ll find a nuance you missed. No need to panic or turn to the answers.

Finally - do as many problems as you can. Keep hammering away. There are very few people who can just read the text and solve any problem - for us peons of average mental faculties we need to keep plugging away at the problems.

Dazed has some excellent ideas for approaching physics.

For me, physics was more conceptual and less intuitive than organic chemistry. That moving tires work using static friction, or that pulling in your arms can make you spin faster due to your moment of inertia - these are counterintuitive to me. It seems that most of intro physics is figuring out which value stays constant and figuring out the rest from there.

If rearranging equations is giving you conniptions, brushing up on your algebra may help.

My classes used “Physics” 2nd ed. by Walker. In that text, I found the “conceptual chekpoints” scattered throughout each chapter to be quite useful - perhaps your book has the same.

Different physics profs seem to focus on different things; some go more for problem-solving, some are very conceptual, etc. The biggest universal - at least with mine - was that all wanted us to understand how the formula reflected the physical world. This seemed like a focus of the MCAT as well. You’ll see this in questions like “Does X vary directly or inversely with Y?” and “Changing which of these values will give the greatest increase in Z?” or “If we double A and halve B, what happens to C?”

Good luck with it! I’m sure it’ll end up being surprisingly doable for you. That Physics thread you suggested might be a good idea, too.

Another useful skill in physics is to draw diagrams of what you are trying to solve for, and then draw what forces are acting on what, and what their values are. It helped me quite a bit to sometimes use multiple colors on practice problems so that I knew what system I was actually solving for and what was external to the system. Hope this helps!

Thanks for your replies everyone.

Yes, brushing off the algebra cobwebs is helping, I’ve spent some time today running through my college algebra book and remembering the basic rules. It’s amazing how we somehow still lose grasp on the basics.

The physics questions I’m dealing with are pretty elementary in their complexity: constant acceleration, time, displacement, magnitude of acceleration, instantaneous velocity/acceleration (which are 1st & 2nd derivitives). Basically, I’m given a few knowns and asked to find a couple of unknowns. The problems seem to be more analitical and less conceptual, although early in the homework sections, there are some conceptual points to be made, but based on my homework assignment, the prof. isn’t going to be spending much time doing conceptual stuff. This is why I outlined the chapter (which is not required) so that I could try to grasp the concepts and not just solve the problem.

I’m thinking of buying Schaum’s Physics outlines at my local Barnes & Noble. I’ve been told that Schaum’s are great books and really simplify things. Don’t know if it’s worth the money, but we’re going to see.

I’ll keep you all updated & thanks for the replies/advice.

-Justin

Justin -

If you are unsure if you want to spend money on Schaum’s, you might check and see if your library has it available for either checkout or closed reserve. If they don’t have it, they may be able to get a copy from another library.

update…

I sat down this evening and used the methods that you all suggested. I sat down & reasoned out the givens/knowns vs. the unknowns/what-they-want-y ou-to-find. I even drew some motion diagrams to help out and darn if I didn’t get every problem right! Rearranging the equations to make them work for you is awesome once you get the hang of it.

I was ecstatic tonight knowing that something as simple as physics I got for a change!

Oh well, one minor victory in the big battle! I’ll keep you all posted and try to keep this thread going.

Thanks again everyone

-Justin

Drill. Drill. Drill. I would avoid spening too much time reading and outlining. You have to spend time working problems.

The Schaum’s outline will most likely be worth the investment. You may also want to consider REA Problem Solvers; plenty of questions to drill with that all build on the previous question.

and here’s a link that may be of use: http://apphysicsb.homestead.com/study.html

grasshopper,

thanks so much for that link and the info. Is the REA problem solvers text available at Barnes & Noble or any other bookstore? I’m seeing that you’re absolutely right about working out problem after problem. You can’t work out one, get it right and think you have it down pat.

Thanks again

Justin

I counted on Schaum’s outline when I was doing physics. I agree w/ grasshopper’s comment that there is no substitute for drilling – more and more problems. I liken it to foreign language by immersion. Just as there’s no point to discussing, in English, how to decline French verbs (or whatever the hell you do with French verbs, I have no idea), there really isn’t much point to TALKing a lot about physics, you gotta DO physics.

On my first physics test – an OPEN BOOK TEST, mind you – I scored below the class average and was humiliated, depressed, and sure that I was doomed. Once I realized that it would all make sense if I did enough problems, I was set. You can do it, too!

Mary

Yes, I think any large bookstore will carry it. I know I’ve seen some of the other Problem Solvers at Borders, etc. I think they are about \$20.

There are a whole series of them: REA Problem Solvers for Calculus, Algebra, etc. They’re oversized paperbacks with up to 1000 pages. It won’t look like much at first; out of date font, plain cover, etc. But they are a mainstay. Every problem is worked out in detail.

One caveat: Each topic will start with an easy problem and then build from there. I believe there is a point where the problems become calculus based. You could stop there and move on to the next topic if your physics class is not ‘calculus based’ (hopefully not, since I don’t think any med schools require that). However that might mean that there aren’t a whole lot of appropriate problems. But for \$20…

If you can’t find it, there are many other books full of solved problems. Just make sure it is one that has been thoroughly edited. You’d be surprised at some of the error riddled stuff put out by Barron’s and the other major publishers.

Hang in there!