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I'm good at algebra physics but I hate calc physics

  • Thread starter Carnivroar
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In my intro to physics course, I have to do both algebra and calculus. I'm doing great at the former, but I have a lot of trouble dealing with the calculus material. I'm pretty good in my calculus classes though.

Should I still pursue a major in physics?
 
If you hate calculus based physics? No. Absolutely not. You will never reach the end of calculus based physics. Even in graduate school you'll still be using calculus.
 
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What do you hate so much about calc-based physics?
 

cepheid

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I don't think it's too strong a statement to say that calculus-based physics is true physics. If you exclude calculus, you restrict yourself to plugging numbers into equations, and you have no way of deriving those equations in order to see why they are true. You are also simply unable to solve all but the simplest of problems.

The main subject of an introductory physics course is usually classical mechanics, which is the study of motion. Part of the reason why Newton invented calculus was so that he could express the laws of classical mechanics. In other words, this mathematics is required in order to describe the laws of motion. Understanding this mathematics is necessary in order to understand and appreciate the physics.
 
In my intro to physics course, I have to do both algebra and calculus. I'm doing great at the former, but I have a lot of trouble dealing with the calculus material. I'm pretty good in my calculus classes though.

Should I still pursue a major in physics?
I've noticed that most intro physics texts (and professors) use uses differentials, the substitution rule, inverse derivatives, and various other things in ways that are almost certain to confuse the average Calculus I student, such that the calculus in the physics material doesn't "feel the same" to them as the calculus they're used to, and they end up feeling like they're on shaky ground.

Sometimes they even just throw complicated calculus at you without really explaining how to think about it conceptually, nor how to solve problems with it in practice. Like for example very early on a text will throw line integrals at you, but won't explain them in any proper way just as mathematical entities in their own right. Or they tell you that center of mass can calculated via an integration, but they completely neglect to even *mention* that you need to use triple integrals to actually do so. And don't even get me started on how hideously they neglect and abuse surface integrals in undergrad textbook material on Gauss's law. So in the end the student is left feeling like there is a lot of hand-wavey magic going on that they really don't quite understand. And the reason is because their Calculus 1 course didn't actually teach enough of the calculus tricks and notations that you need to know to understand calculus based physics, and the tricks are actually pretty simple if someone presents them to you in a straight up pure-math sort of way without mixing in any of the physics related ideas until you're ready.

So if it is the above sort of things that you're having problems with, then perhaps post about the specific calc-based physics theorems that are confusing you, and I'm sure you'll get great explanatory responses. (Or even PM me whenever you do make such a post, and I'll be sure to chime in with my own explanations; which I not surprisingly happen to think are pretty good).
 

eumyang

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And the reason is because their Calculus 1 course didn't actually teach enough of the calculus tricks and notations that you need to know to understand calculus based physics...
This reminds me of how in some schools, Calculus I is a prerequisite for Physics I, while in other schools, Calculus I is a corequisite for Physics I. While having Calculus I as a prerequisite sounds logical to me, I am sure there are reasons why schools still have it as a corequisite.
 
This reminds me of how in some schools, Calculus I is a prerequisite for Physics I, while in other schools, Calculus I is a corequisite for Physics I. While having Calculus I as a prerequisite sounds logical to me, I am sure there are reasons why schools still have it as a corequisite.
I think this is for getting physics majors into physics classes right away. I think maybe, however, it does the department (and retention) a disservice. Some people crash and burn with Calc I as a corequisite.

In my experience, I started the physics sequence late (i.e. after Calc I) because I didn't come in declared as Physics (but rather as Chemistry)... and I honestly think it helped. I'd then completed Calc II (integration) before the calc-based EM class (which rather depends heavily at least on the concept of integration, ven if you keep the actual integration easy). Of course some people CAN handle the courses simultaneously. But I always found that being ahead in math did me VERY well.
 

cepheid

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victor.raum,

My experience was much the the same as yours, esp. regarding being expected to somehow just work with line integrals as though they weren't something new that we didn't even have a definition for. It's amusing how they have no qualms about giving you some of Maxwell's equations in integral form in first-year physics texts, but they'll NEVER give them to you in differential form (at least not the full 3D versions) because "that crazy upside-down triangle symbol" would just freak people out, whereas a line integral is deceptively familar-looking and hence they feel they can just throw it out there.

I'll also never forget in first year physics discussing SHM:

[tex] \ddot{x} = -\frac{k}{m} x [/tex]

Prof: "Well, this is a 2nd-order differential equation, and you have no idea how to solve it. Fortunately, in this case, we can just guess the solution." :rofl:

On the other hand, sometimes it's helpful to be introduced to new math in a physics concept first. By the time Calc II rolled around, I felt comfortable with partial derivatives already, because I had first been introduced to them in the context of the wave equation. It was helpful to hear the explanation that the wave intensity was a function of *both* position and time (two variables) and that taking the partial deriv. w.r.t. position, keeping time constant, was like taking a "snapshot" of the wave at a certain instant and seeing how the slope of this fixed waveform varied as you moved along it. Similarly, taking the partial deriv. w.r.t. time, keeping position constant, was sort of like sitting a fixed point on the wave and seeing what the rate of change with time of your displacement was *at that point in space* as the wave passed across you. This was a nicely intuitive example.
 

mathwonk

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let me encourage you to persist in calc based physics. it will get easier and easier as you go along, and not only will the calc make the physics easier, but the physics will illuminate the calculus. give it time. eventually you will be very glad you did.
 
Thanks for the replies.

Don't get me wrong, I love calculus by itself. I got an A in calc 1 and a 96 on my first calc 2 exam. I really enjoy the stuff.

I also love physics, but really only the algebra part. I understand the concepts and I'm not a "just plug it in to an equation" type of guy.

My course is complicated. Let me try to explain. Because our physics department is so small, we physics majors have to take physics with the non-majors (algebra based physics required for other science majors). And on top of that, we get 1 hour a week of a calculus based session that builds on top of what we learned in the algebra session. And since too little time is spend with the calculus material, I'm having a lot of trouble keeping up with it. So maybe I shouldn't say that I hate it, but it's frustrating because I can never do the homeworks. The algebra course counts for most of the grades so I am confident that I can get at least a B+, but I don't know what to expect from the next classes.

I think it might get easier. I remember back in calc 1 I used to get extremely frustrated with the notation, could even figure out what d/dx meant, etc... because it was the first time I was seeing the material. Then I got an A.

We use the Giancoli textbook, by the way.
 
I've noticed that most intro physics texts (and professors) use uses differentials, the substitution rule, inverse derivatives, and various other things in ways that are almost certain to confuse the average Calculus I student, such that the calculus in the physics material doesn't "feel the same" to them as the calculus they're used to, and they end up feeling like they're on shaky ground.

Sometimes they even just throw complicated calculus at you without really explaining how to think about it conceptually, nor how to solve problems with it in practice. Like for example very early on a text will throw line integrals at you, but won't explain them in any proper way just as mathematical entities in their own right. Or they tell you that center of mass can calculated via an integration, but they completely neglect to even *mention* that you need to use triple integrals to actually do so. And don't even get me started on how hideously they neglect and abuse surface integrals in undergrad textbook material on Gauss's law. So in the end the student is left feeling like there is a lot of hand-wavey magic going on that they really don't quite understand. And the reason is because their Calculus 1 course didn't actually teach enough of the calculus tricks and notations that you need to know to understand calculus based physics, and the tricks are actually pretty simple if someone presents them to you in a straight up pure-math sort of way without mixing in any of the physics related ideas until you're ready.

So if it is the above sort of things that you're having problems with, then perhaps post about the specific calc-based physics theorems that are confusing you, and I'm sure you'll get great explanatory responses. (Or even PM me whenever you do make such a post, and I'll be sure to chime in with my own explanations; which I not surprisingly happen to think are pretty good).
That does sound like my problems. I will try asking for specific homework help in the future.
 

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