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MCAT-Physical Sciences. Advices and Tips

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Hi Guys,

About a month ago I received multiple private messages from several PM101ers about how I studied for the MCAT. I promised them that I would post something on the forum. Since I have some time now, I decided to post this thread focusing on preparing for MCAT physical sciences (PS). Other sections will come later.

Before I go on further, I want to emphasize that the tips below are by no means the most efficient way (or, for that matter, the one and only way) of preparing for MCAT PS. These reflect the way I personally prepare for my MCAT physical sciences section, so of course take everything I write with a grain of salt.

Now the Prep:

Physics:

1. The pre-reqs are a must. You need, as a minimum, physics 1, physics 2, calc 1, and calc 2. When I say Physics 1 and 2, I am talking about calculus based courses. I would strongly recommend knowing some stuff in calc 3 as well. Some of the stuff in calc 3 comes in very handy.

2. Physics isn't about "knowing what equations to use in what time." If you focus on that, you already lost the battle. You should be able to derive almost all equations you use in physics with ease at this level. The vast majority of derivations require a strong background in both differential and integral calculus (and sometimes, vector calculus), so know your calculus.

So why spend the time to derive equations you ask?

i) Without deriving equations for yourself you will never know the true limitations of each equation you use, hence falling into the trap of "don't know what equation to use at what time."

Let me give you an example.

W (work)= Force vector * Displacement (dot product)

If this is the way you understand work, your understanding of physics is still at the algebraic level.

W (work) = S ( vector path integral) F(t) *ds (displacement )

In other words, the first equation only holds when 1) force is constant (i.e F(t)=constant, pulling that out of the integral). 2) angle is constant (hence pulling costheta out of the integral).

Your understanding of physics should not be stuck at the algebraic level. By this time, you should understand physics in terms of calculus (which is what physics is to start with).

So, try deriving every equation you use. There will be a couple that you probably won't be able to derive at this stage (esp. magnetism, statistical thermodynamics, quantum stuff...etc) unless you have taken calc 3 in full and a upper year course in calc-based statistics, so obviously don't worry about them. Use common sense when you approach this.

This may take a while especially if you haven't studied physics like this to start with, but it's worth it trust me!

3) Do problems. Lots and LOTS of problems Start with problems in your physics textbook. Skip the easy ones which require basically you plugging you a few numbers (or a slightly more complicated version where you combine a few equations then ended up plugging in numbers anyways). Do the hardest problems in your physics textbook. Those are often the last 3 or 4 questions in each chapter. Those questions are conceptually and mathematically harder than MCAT Physical Sciences by a significant margin.

As you test date approaches (2-3 months ahead), start doing MCAT style passages on top of textbook questions. By 5-6 weeks till test day, you should do only MCAT passages obviously.

4) Memorize as many of the frequently used constants as you can (obviously don't go overboard). Yes, everyone will tell you that this is absolutely unnecessary. However, the more constants you know by heart the faster you move through the passages.

5) Know how to simplify your math. g in MCAT is 10 m/s2 not 9.8. Know your trig values by heart (i.e sin45=1/sqrt(2)=0.7 and so on). Get used to only substituting numbers in an equation at the very end rather than at every single step. Work well with exponentials.

6) Your understanding of physics should be conceptual (i.e know why the equations are there....derivations again!) rather than mechanical.

General chemistry:

1. Pre-req: General Chemistry. Strongly recommended: some qualitative inorganic chemistry class (some schools have it as gen chem 2) .

2. Same stuff as physics really. Know why the equations are there instead of being stuck in the trap of "when should I use this equation"

3. For gen chem, deriving equations isn't as important in my opinion. However, try to understand where the equations come from and the possible limitations.

4. No need to do the textbook questions. Focus on MCAT passages here.

Again, take my advice here with a grain of salt. These advices only reflect how I personally studied for the section.

Best of luck and regards,

much thanks !

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thanks.

a question, For the most mcat-physical sciences, r they split 50/50 between chemistry and physics passages or it could be different by 60/40 depending on when the test is taken?

I know for biological sciences there is more biology passages in it.

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I wouldn't worry about the split. I didn't notice a weighting towards bio in bs at all.

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there are some figures floating around that suggest it's 50/50 for ps and 70/30 bio/orgo for bs. but, yeah, i wouldn't worry about the exact split that much. they *should* be what i mentioned though, on average. so yeah you could see some 60/40, but is that really that different? (calling all statisticians, kidding).

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are you suggesting that you cant take the mcat and do well without having finished physics as prerequisite. Cuz thats basically my plan :(
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it's very helpful to have at least hs physics, and maybe first year physics. but as a ton of others have said, it's not impossible. get your hands on solid prep company's book if you can (i mention that solely because they've sculpted their material to include all things mcat, and nothing else. so, a diff text would work, but wouldn't be specifically made for your needs). geography, music, and english majors manage to get into med, so meh.

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are you suggesting that you cant take the mcat and do well without having finished physics as prerequisite. Cuz thats basically my plan

Don't get discouraged. I think the OP makes some great points about the certain prereqs and your ability to understand the limits of the equations you're using. If you can understand the limits to the fullest you can derive any equation you need to fit the scenario you are given on the MCAT physical science section. OP has obviously got an amazing hold on math and how physical equations and laws connect to each other, and is further supported by his outstanding score of 15 in PS.

However having said that, you really "only" need an 11 (still not very easy ) in the physical science section to meet every cutoff of Ontario med schools. I think with adequate studying and a decent aptitude for math you can score near this.

There are plenty of non-trads who have never taken physics and done extremely well on the physical science section. That doesn't mean that it's easy; you need to bust your ass and do a ton of practice to nail down the concepts to attain mastery of each topic. I'm a fairly non-trad with the physical sciences (took only half physics and half G Chem, no calc) but I have studied a **** load everyday and have attained a good understanding for the majority of topics in PS.

You can do it! Keep practicing, it will come .

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I'm gonna go ahead and say that for PS, calc is almost useless. yes you'll know how to derive the Energy questions from the Force equations. but calc 1, 2, 3? no way. even calc-based physics is not required at all. my physics course used calc to derive magnetic and electric field stuff. didn't help me one bit for mcat.

but understanding equations, and having an insight into what the equations mean in the real world makes a huge difference. the equations tell a story about how variables are inter-related and how they affect each other. they're not things for you to plug numbers into and get magic answers back.

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I'm gonna go ahead and say that for PS, calc is almost useless. yes you'll know how to derive the Energy questions from the Force equations. but calc 1, 2, 3? no way. even calc-based physics is not required at all. my physics course used calc to derive magnetic and electric field stuff. didn't help me one bit for mcat.

but understanding equations, and having an insight into what the equations mean in the real world makes a huge difference. the equations tell a story about how variables are inter-related and how they affect each other. they're not things for you to plug numbers into and get magic answers back.

Totally Agreed. I mean, I have Calc 1, 2, 3, 4 as they are all required for honours chem, intro calc up to differential equations and multivariate calc. Actually have calc 5 (or what we call calc 5 here, which is a 3rd year extension of differential equations. And essentially none were useful for the MCAT PS. Could I have wen't through the derivations in great mathematical detail, yes, did I bother, no. Having insight and intuition is important, and maybe the math background played a role there, who knows. I believe the constant building of logic and problem solving ability over the past years in a physical science field was FAR more useful. Sadly, that's not easy to do in a summer.

Also, I didn't take first year physics in first year because it conflicted with some second year Bio classes I wanted to take and I didn't get around to completing it before I wrote my MCAT. Self-teaching is possible (good friends in physics help too ).

Not to discredit the OP's comments though, intuition and a deep understanding goes a long way in helping you work your way through problems that you don't immediately understand. Seems like a legit direction, just maybe a little over-kill imo.