So You Want a Degree in Physics

I occasionally get comments and personal messages from people who say that my work has helped inspire them to pursue an education in the Natural Sciences these are by far my favorite type of messages to read they're often accompanied by requests for advice on how to proceed how to prepare how to stay focused motivated and so on I decided to make a video to try to cover all basis in a comprehensive and helpful fashion so I'm going to tell you how to become a successful physics major and what you can expect if you choose to take this path the first thing that I need to point out is that it doesn't matter how old busy or poor you are if he wanted badly enough you can have it provided that you work for it one of my classmates is a fat 30 year old who works two jobs has kids and still manages to attend every lecture and pass every exam there is always a way to succeed if you're dedicated enough and nobody will think any less of you if you choose to take a path that you might feel is undignified like transferring to a university where every student has half your age after being stuck in a small town community college for seven years there is no such thing as an undignified path to a physics degree unless of course you got that degree from Bob Jones University the second thing that you need to know is that you're going to need a lot of math and I mean a lot of math trying to do physics without math is like trying to drive without gas in the tank you're just not going to get very far the good news is that with enough work and dedication you can learn math regardless of how bad you are at it I used to suck at math until I figured out how to learn it properly how to study the right way and get the most out of the time I spent trying to understand the material in a moment I'll dispense some of these tried-and-true methods it used to be that I scraped by with C's in middle school algebra now I'm playing around with the spherical harmonics and group Theory if you want it badly enough you can have it provided that you work for it the next thing that I should tell you is that as I think it goes without saying learning physics isn't easy there's a certain way to approach physics problems a certain style of thinking that needs to be adopted you see doing physics is more than just deriving the equations and accounting for variables doing physics is the art of problem solving it's for this reason that physicists are so sought after in almost every industry it's not that we're geniuses or anything it's just that we know how to solve problems which is a very rare skill that unfortunately cannot be taught in the classroom or read from a book you can read a physics textbook until the cows come home hell you can even go ahead and memorize every word in it but you still won't learn how to do physics unfortunately the only way to learn how to do physics is by doing physics it's like learning to play the guitar reading instruction manuals and listening to other people play just isn't enough if you want to learn how to play the guitar you're going to have to pick up a guitar and start playing when it comes to doing a physics problem there are two main steps setting up the necessary equations and solving them solving a physics equation is easy enough but the part that won't come naturally to you is setting it up I can confidently say that it's this aspect of physics that's the most difficult ask any physics major and they'll tell you the hardest part about physics isn't the concepts the hardest part isn't even the math the hardest part of doing physics is turning a word problem into a math problem once you do that the rest is what we sardonically like to call just math it's hard to appreciate just how difficult and time-consuming physics can be until your feet are actually put to the fire there is nothing that I can say that will adequately prepare you for the intensity of the subjects learning process but with determination and perseverance you can learn it if you want it badly enough you can have it provided that you work for it finally I should point out that the more you learn the stupider you feel it's a strange feeling and it's not entirely bad but the more you learn physics the more you can appreciate just how vast and insurmountable the mountain of knowledge is some people are higher up on this mountain than others but the higher you climb the more of the mountain you see and the more you come to understand the overwhelming futility of trying to climb to the top within one lifetime most of us look at men like Stephen Hawking as those who have reached the peak of this mountain when in fact people like him have a better understanding than anyone else of how little one knows first of all you need to be fluent in algebra geometry and trigonometry when doing calculations involving these maths you shouldn't even hesitate some excellent resources for brushing up on and learning these topics cold or Khan Academy and Patrick JMT which pump out amazingly concise videos that you can use in combination with any math textbook that hasn't been printed by Bob Jones University in fact Khan Academy and Patrick JMT are life saving resources that can be used for everything that I'm about to say I cannot tell you how many exams these men helped me pass as a result of their tutelage also very useful is Paul's online notes which lay out all of the following branches of math in a very cohesive manner after the basic math has learned you need to learn single variable calculus learning how to take a derivative and how to integrate what these mean physically as well as mathematically and which situations are appropriate for implementing these methods is essential to doing physics your understanding of physics will let best be superficial if you don't understand calculus what's more you need to know calculus cold taking the derivative should come as naturally to you as doing this you should be able to do calculus in your sleep at some point in your mathematical education between learning how to integrate and how to solve partial differential equations which comes much later you'll need to learn sequences series and convergence tests which all show up at some point or another in physics especially important is learning Taylor and Fourier series as these are absolutely indispensable tools to have in your mathematical arsenal after you learn how to differentiate and integrate single variables you need to learn linear algebra linear algebra takes the ideas of high school algebra and generalizes them to as many spatial dimensions as one pleases as far as mathematical concepts go nothing in basic linear algebra is really all that new it's merely a reform ization of algebraic concepts into a more useful form with new definitions and new operations that yield very useful results there's usually no calculus involved unless you're taking a more advanced course in this topic but that's unnecessary after that one usually learns differential equations which is probably the most useful branch of math out there first you will learn ordinary differential equations which involve concepts learned in single variable calculus plus a little bit of linear algebra differential equations are extremely useful because they allow us to take complicated physical situations and formalize them in a way that can be analyzed for example let's look at a classical problem that shows up in the theory of differential equations suppose a 1500 gallon tank initially contains 600 gallons of water with five pounds of salt dissolved in it water enters the tank at a rate of nine gallons per hour and the water entering the tank has a salt concentration that conforms to this function of time if this liquid leaves the tank at a rate of six gallons per hour how much salt is in the tank when it overflows without differential equations you would have nowhere to even begin it's a situation that's easy enough to imagine but impossible to solve without advanced mathematical methods after one learns ordinary differential equations you'll have to learn partial differential equations but first you'll need to learn multivariable calculus which takes one dimensional calculus and generalizes it to multiple dimensions once that's done it's essential to not only learn basic methods of solving partial differential equations like separation of variables and the method of characteristics but more advanced methods like the power series method and integral transforms especially Laplace and Fourier transformations in general though when confronted with a partial differential equation in a physics problem the separation of variables method is the physicists first line of attack it's at this point that you'll no longer be able to use Khan Academy Patrick jmt and Paul's online notes because they don't teach the more advanced mathematical methods that I'll be introducing now everything that I've described up to this point is what one might call baby maths from this point forward things begin to get more serious and I'd recommend using YouTube channels like MIT OpenCourseWare and dr. Chris Tisdell to learn some of these subjects one not so difficult but extremely powerful branch of math that I'd urge you to learn as complex variables which includes complex analysis conformal mapping and integral transformations the methods introduced in here are very good to learn and will be extremely useful in several branches of physics finally the math that should know is calculus of variations which involves functionals and isn't too difficult to figure out once you know the basics without calculus of variations you cannot do advanced classical mechanics from here on out the type of physics you're interested in will determine the type of math that you should study do you like thermodynamics Golar and information theory are you into fluid mechanics chaos theory is the way to go do you think that string theory is the go learn knot theory if you're like being are really into particle physics group theory is absolutely indispensable if you're also like me and think that general relativity is the coolest ever then tensor calculus differential geometry and general topology are essential there are many many options in physics and correspondingly there are many many routes that you can take in math so now that we've talked about the mathematical journey what about the physics journey it's customary to begin by learning introductory classical mechanics which includes kinematics which is the study of how things move and dynamics which is the study of why things move at this point it's a good idea to at least have had some experience with calculus differential equations are likely to show up especially when considering the harmonic oscillator and wave mechanics but it's unlikely that you'll have to solve them at this stage of your education after linear kinematics and dynamics are learned angular kinematics and dynamics usually follow followed by basic fluid mechanics and basic thermodynamics then classical electromagnetism is taught beginning with classical electrostatics and electrodynamics followed by magnetism it'll be at this point that multivariable calculus will become crucial after magnetism is learned the dynamics of electromagnetic waves will be introduced followed by basic optics after this point one might learn special relativity once all of this is learned you should also know the basics of partial differential equations and every math that preceded it in other words you should be done with the baby math it generally takes about two years to get to this point from here the advanced physics courses will vary from university to university but they will all include advanced mechanics advanced electromagnetism advanced thermodynamics quantum mechanics and any number of specialized courses like particle physics cosmology general relativity condensed matter physics advanced optics nuclear physics plasma physics astrophysics nonlinear phenomena statistical mechanics and so on there are so many options to choose from that it would take me forever to list all of the topics associated with physics I'm going to operate under the assumption that your physics education will be based on the standard lecture format so rule number one always attend lecture this might seem obvious at first sight but you'd be amazed at how many people skip out of the lectures because they think that they can cram all of the necessary information right before exams and that usually doesn't work so I'd recommend against it always go to lecture and take good notes this usually means copying whatever the lecturer writes on the board and listening to their explanations of what's going on rule number two skim the textbook just before class you don't need to read the whole thing but it's a good idea to read the relevant sections or chapters that will be covered in the lecture in the beginning of the course you'll usually be given a syllabus which should assist you in deciding what to read before class rule number three take careful notes while reading the textbook reading through a math oriented book is not like reading other types of books highlighting important passages and writing down important concepts isn't usually the best policy what you should do is pencil in hand read through the text carefully and outline the logical and mathematical progression of ideas in each section important equations should be highlighted or boxed and the derivations of these equations should not just be copied but understood line by line learning how each step is related to the previous one is essential to understanding rather than merely memorizing a derivation some equations like Schrodinger's equation or F equals MA should be committed to memory others like the adiabatic work expression should be understood to the extent that you know how to use it and where it comes from so that you'll be able to derive it should the situation call for you to do so but generally this is the sort of thing that you should refer to in your notes things like this shouldn't be memorized as your experience physics grows you'll become better at distinguishing essential equations from non-essential ones rule number four do example problems typically physics textbooks will give you example problems after covering a certain topic the book will show you a situation and will show you how to set up a mathematical equation that models the physical situation at which point you can go ahead and solve for whatever physical variable you're looking for it's a good idea when solving physics problems to leave everything in variable form until the very end it's easier to work with abstract mathematical expressions than it is to juggle a bunch of numbers and units around and in any case doing the former lets you see what's going on much more clearly and helps you understand how different physical variables relate in addition to example problems which hold your hand all the way through the solution there are exercise problems whose solutions you have to figure out on your own these are the problems that show up in your homework or recommended exercise lists and the most obvious policy for how to deal with these things is rule number five don't leave homework to the last minute not because procrastination is a bad thing in and of itself but because the last minute rush will force you to try to get your work done before the deadline without having much regard for what you're learning you'll be so desperate to get the work done on time that you'll end up missing out on the skills needed to actually work through and understand the physics which is the whole point of the homework in the first place often times homework will contain a variety of problems as far as the difficulty level is concerned so if you can consult with your professor teaching assistant or an online resource to help you with nastier exercises before you do any of that though you should probably consult with a classmate I say a classmate as in singular because rule number six study in pairs research has consistently shown that when studying something and this is especially true for physics and engineering the ideal size of a study group is two people not one not three but two trust me on this if you want to get the most out of studying do it in pairs I cannot stress that enough rule number seven study for tests the right way usually the ideal time to start studying for a midterm or a final exam is a week and a half to two weeks prior to the test start earlier and you run the of moving so slowly that you forget the things that you review in the beginning and waiting until the weekend before is a very very very very very very very very very very very very very very very very very bad idea usually the right way to study for an exam is to reread the relevant parts of the book going over your notes from the lecture and the book and redoing all of the preceding homework what's essential here is pacing yourself so that all of this has accomplished over the course of about two weeks oh and don't forget to study in Paris if you follow all of these rules to the letter then I can guarantee at least an a-minus in any physics class that you take well that's all I've got I wish you the best in your academic pursuits and I hope that you'll consider going to school and majoring in physics it's a tough ride but it's also quite rewarding I'll leave some resources in the description box below for anyone who wants to get a personal taste of what a physics education will entail you

Channel: King Crocoduck

Views: 654,060

Rating: 4.8828712 out of 5

Keywords: physics, science, education, college, university, quantum, electromagnetism, classical mechanics, particle physics, condensed matter physics, carl sagan, michio kaku, neil degrasse tyson, stephen hawking, bill nye, knowledge, higher learning, stem, cosmology, optics, nuclear physics, plasma physics, chaos theory, relativity, astrophysics, nonlinear phenomena, continuum mechanics, fluid mechanics, statistical mechanics

Id: Kk8q500rYo4

Length: 16min 54sec (1014 seconds)

Published: Mon Apr 13 2015

Reddit Comments

[u/BadgerFlame]

As a 29 year old who recently returned to education to acquire a physics degree. I actually found this really motivating rather than daunting.

[u/spectreid]

so far I follow pretty much all of his steps about how to study and it and it seems to work fine for me although I could do better if I started to learn for my exams more early.

The only thing I don't like to do is study with a classmate because I always feel like they're just slowing me down with my progress even though I know that when I explain stuff to them or the other way around it adds much more to the understadning of the material for both of us than if I'd study all by myself :/

[u/ncryptdntllgnc]

Not to discredit anything he is saying but is he just showing off?

It is a good summary of the things you learn, though.

Edit: Probably shouldn't have commented prematurely. His advice on how to study is spot on. Just the 'listing all the math and their fancy names' part seemed kind of unnecessary for an audience that has not even started a degree yet.

[u/sutaeji]

It's all about Griffiths E&M and Griffiths Quantum!

[u/vicecircle]

It's a little weird that he used a picture of people praying in a mosque when he talks about kneeling in the valley of ignorance.