Why Do I Suck at Physics Conceptually?

[MissionStanford]

The math isn't the problem. I'm good at math. The problem is conceptual understanding. In physics 1, I aced the first test (topics like Newton's laws, kinematics, etc.) but did poorly on the next 2 (topics like torque, angular momentum, waves, etc.). I haven't taken physics 2 yet but heard it's much harder.

I've been able to conceptually understand all other subjects I've taken in math and science. I have an ok grasp of physics concepts but not nearly as solid of a grasp as I'd like. My physics teacher had a heavy accent and didn't really "teach", so that didn't help.

We used the Halliday and Resnick textbook, which also didn't explain concepts well in my opinion. I've tried using the Princeton Review MCAT Physics book, which explained concepts pretty well but doesn't go into that much depth. I've tried Khan Academy videos, but I didn't find them all that helpful. What can I do? I've heard Nova is a good book.

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[DAVIDBOWIE]

For me, a conceptual understanding of Physics is less natural than with Biology or even chemistry a lot of the time. It just so happens that some of the concepts are bit more abstract in Physics. I have found that the best way to overcome this is to make analogies between physical processes and other things that I do understand well. An example would be resistors in parallel as apposed to series. There is a great analogy to water running through a river and there are two water falls. Do you know that one? Things like that help me visualize the concepts and then after you hammer it in enough it just sticks. I wish I could get a little better at the math myself

 

[brood910]

Do you COMPLETELY understand vectors?
You should not just memorize the equations but understand the concepts.
Ask yourself "why"s when you study.

 

[manchika]

I exactly understand your frustration... I am in the same boat... I feel I understand the chapter but when I get to the passages, I am lost , I do not remember what to use, why to use, where to use... nothing... Mind goes blank on me...

I am not of much help for you but I will sure be using those suggestions that others give you....

Good luck to you with Physics

 

[Integrated MCAT Course]

In my experience many folks who have difficulty with a conceptual understanding of physics have only learned to see the formulas as plug-and-chug machines for solving quantitative problems. Physics formulas are not about processing given information to produce a number answer. This point of view is a by-product of the 101 lecture course. Try instead to see each formula you encounter as a kind of language. This will help physics become a part of your common sense and make MCAT passages and questions much more coherent.

Just like a verbal sentence with a subject and a verb, a physics formula is a representation of reality. What does a formula tell you? First, when you study a formula, try imagine the simplest field of reference that it can encompass. This is the model system for the formula. For much of mechanics the model system is simply an object on a frictionless surface; in electrostatics the system you try to imagine consists of charged particles suspended in a vacuum, or between parallel plates, in thermodynamics, it's a sample of ideal gas within a piston. This model system comprises the field of reference that the formula refers to with physical quantities.

Now, imagine things changing in the system. If time appears in the formula, let time increase and imagine the other quantities changing. Imagine your model system and try to give the physical quantities substance in play within your imagination of change. What does the formula tell you happens if the diameter of the pipe changes, the piston compresses, or the two charges are brought near to each other? If it's conservation law, how does the over-riding fact that some things remain the same help you interpret changes that occur?

Practice this with each formula. Try to put the formula into words. Imagine the model system it represents. Put it through changes in your mind and draw conclusions. The trouble you are having is very common. You just need to overcome a confusion between doing well in Physics 101 and applying physics as a framework for looking at physical phenomena and understanding the interactions and changes that can occur.

 

[Sarvish]

I haven't taken the MCATs yet so I'm not sure how useful the advice will be but I'm in a physics major so I've taken advanced physics courses and done pretty well in all of them.

I think the main thing is that you need to never move on from a topic until you've got the basics down. I've always found that each topic needs a few fundamentals that you need to completely understand and then everything from there falls into place.

Let's go with basic kinematics, the things that I thought were really key were:
1) During one phase of motion, acceleration WILL NOT CHANGE. Seems obvious but then people always trip up at the fact that a projectile at it's highest point has a non-zero acceleration. Velocity and displacement will change but acceleration will not, write acceleration somewhere and underline it and make sure you don't change it.

2) If acceleration changes, break the problem up into smaller steps. Treat it as separate chunks to the same motion. Do not assume acceleration changes unless you are specifically told it does.

3) You'll always have 3 of the 5 necessary parts for each kinematics question. The trick is finding them. Good spots to look: acceleration might be implied as gravity, v0 might be 0 if the object is starting at rest, v0 might be the vf from the previous chunk of motion, distance might be the same as the previous chunk of motion if you're going down the same path in the opposite direction.

I realize kinematics is the easiest one to go with, but I like to do this with all topics, just find out what information we need, where to get it from, and why it works.