Why is Physics So Hard? Advice to Improve

[Angry Citizen]

I used to think Math and Physics were really difficult subjects. I almost failed Calculus and did terrible at physics...now they are my favorite subjects. How?

The reason you are finding it difficult is because you are failing to grasp the "big picture". I found out that there are NOT an infinite number of math or physics problems. They usually fall into into one category. They may have different numbers and circumstances but if you recognize the TYPE of problem it is you will ace the test.

If you follow this plan you will succeed. After I understood this I retook calculus and other advance math and physics and aced the courses in the high 90s.

Step 1. Realize that the new material will NOT continue to come. There is a finite amount of material to learn. In fact you will find the first year or two of college more difficult than the advance stuff (in any subject)...because you first need to learn the basics. Before starting the book - scan through the entire book (use the index). Before starting a chapter - scan it to get an idea of what's coming. Before going to class (do STEP 5).

Step 2. Take the time to do each problem - including ALL the problems at the end of the chapter ...but most of all do this in conjunction with STEP 3

Step 3... Memorize. Whoever said that you cannot memorize math was dead wrong. The first book you should read before doing anything else is a book on memorizing stuff. There are a ton of them out there. Once you learn the techniques memorize:\

i) formulas and constants
ii) create a system for memorizing the TYPES of problems you are likily to encounter


Step 4. The next step is probably something that you should do upfront. Essentially you need to get really excited about each course you take...even if you're a premed student and don't think you'll ever need any of this. Find reasons to get really excited!

Step 5. Learn the material BEFORE you go to class. I found that if you go to class you can easily get behind (especially if you have a lousy prof who can't talk). Learn the lesson ahead of time...do the problems before hand. The class should essentially be a review. It can also help if you had some problems - the class should be a great place to ask the prof to clarify things. Also if you have a question (because you're confused about something) chances are a lot of other people don't understand...even if you glance around the class and everyone looks confident - they probably don't have an idea of what's happening.

Good luck!
Phil

Step 3 is absolutely terrible. Since when did Physics become an exercise in memorizing formulas?

 

[lrl4565]

I find physics... occasionally frustrating. I have so many questions! How to get them all answered? I don't know, but that thing about just memorizing the formulas may actually be a step in the right direction.

I've heard that high school physics is basically background stuff. You have to just assume that it is right and move forward. When I hear equations like "Force = mass x acceleration", I want to ask, "why?", but then it becomes IMPOSSIBLE to move on. So, it's best to just assume that it is correct and work on that assumption.

You said you were working on projectiles now? Well, it's all trig! Hypothetical scenario:
You launch a rocket at 100 m/s 60 degrees up. Now, what do you imagine in your head? Why, a triangle with x length on the ground, y length straight up from the ground, and a hypotenuse of 100. Can you use trig to find the x and y lengths? 100cos60 = x m/s, 100sin60 = y m/s. Okay, that is just the predicted path. Now you must factor in gravity.

Gravity works straight down, so x m/s is not touched AT ALL. Only worry about how it affects the y. You can determine the highest point of the projectile by figuring out when the downward velocity of gravity is equal to the upward velocity y m/s.

 

[Chunkysalsa]

If you understand the concepts then after doing a lot of pratice problems the answer becomes really easy to solve. Like that guy says the questions usually end up the same. No need to memorize anything though.

Especially in projectile motion, if you understood 1-D motion then its just two 1-D problems. Write down what you know, what you need to know, what formulas you have and draw a picture. At that point it usually becomes clear on what to do. If you have 2 unknowns and 2 equations to solve them then at that point its all algebraic manipulations.


and I have to agree on that grade inflation thing. In my high school AP classes they have this unbelievable curve on everything. I would make A/B on all the test but not in reality, college isn't like that (most of the time lol) so it really dumbs people down.

Exception was AP Biology. that class was actually hard and according to a pre-med friend of mine, it was actually harder than college bio.

 

[Andy Resnick]

If you don't pay the the college instructor, then how do you expect to get let into the educated club?

That's exactly the wrong approach to education. Certainly, it's possible to educate oneself, and not just in Physics.


Atyy's answer is better, but vague- what's 'good teaching'? Here's what I expect, when I pay for tutoring:

1) An initial assessment, indicating specific topical areas that need improvement
2) periodic assessments, providing feedback and indicating progress (i.e. 'formative assessments')
3) a final assessment, showing a measurable improvement in subject mastery ('summative assessment')
4) answering my questions in a manner I can understand
5) providing access to supplemental materials as needed
6) having set contact hours

Note what's missing: I'm not paying to 'learn'. The responsibility for learning the material (and doing the work) is mine. I'm paying for *more efficient* learning.

 

[General_Sax]

That's exactly the wrong approach to education. Certainly, it's possible to educate oneself, and not just in Physics.

Sure it's possible to educate oneself, but who is going to take you seriously?

I taught myself Circuit Analysis on the resume doesn't really mean ****.

Having a degree in EE on the otherhand...

 

[Andy Resnick]

Sure it's possible to educate oneself, but who is going to take you seriously?

I taught myself Circuit Analysis on the resume doesn't really mean ****.

Having a degree in EE on the otherhand...

I think you are confusing credentials with education. Going to college and getting a EE degree is more efficient than learning the material on your own- and that includes *identifying* the required material.

 

[planck42]

Step 3... Memorize. Whoever said that you cannot memorize math was dead wrong. The first book you should read before doing anything else is a book on memorizing stuff. There are a ton of them out there. Once you learn the techniques memorize:\

i) formulas and constants
ii) create a system for memorizing the TYPES of problems you are likily to encounter

Ah, but what if you should forget something? That is the downfall of the brute memorization approach. imo it is much more important to be able to reconstruct physics from a basis of axioms(axia?) and mathematical tricks.

 

[atyy]

I think you are confusing credentials with education. Going to college and getting a EE degree is more efficient than learning the material on your own- and that includes *identifying* the required material.

Although your vision is idealistic, isn't what General Sax says sometimes (often?) the reality? If one goes to university, and teaching is horrible, can one get one's money back? If one learns the material to the same level sitting at home, will employers look on you as favourably as the guy who went to the university with horrible teaching?

 

[G01]

College KIDS?

Well said...

 

[atyy]

The demand for good teaching has nothing to do with college KIDS. It is an ethical issue.

 

[NeedsHelp1212]

Im in high school by the way, not sure how we got to this college argument..lol

So i have a test Thursday on the entire chapter. I will definitely use the advice given. And as a poster stated, write down all of the known variables, then the unknowns, draw a picture, and relate it to an equation

By the way we were doing this do now question to day; A golf ball is hit with a velocity v subscript 0 at 30 degrees over a displacement of 150 meters. What are V subscript 0, total time in air, and max height? I got the answers and everything but for one of the equations; change in y= Viy * change in time + 1/2 ay (change in time) squared
What exactly does Viy mean? Probably a real dumb question but I am confused with the i and the y and where it fits on the picture

 

[Angry Citizen]

What exactly does Viy mean? Probably a real dumb question but I am confused with the i and the y and where it fits on the picture

Viy means initial velocity in the y direction.

 

[NeedsHelp1212]

so on the picture when we created our triangle, that would be represented as the vertical component? It would be easier if i could show you the picture

 

[Angry Citizen]

Yes, typically the y direction implies the vertical direction.

 

[General_Sax]

Make sure you understand this:

http://en.wikipedia.org/wiki/Pythagorean_theorem

a^2 + b^2 = c^2

a,b and c don't HAVE to be distance/length. They can be velocity and other stuff too.

 

[Andy Resnick]

Although your vision is idealistic, isn't what General Sax says sometimes (often?) the reality? If one goes to university, and teaching is horrible, can one get one's money back? If one learns the material to the same level sitting at home, will employers look on you as favourably as the guy who went to the university with horrible teaching?

I'm not denying that many jobs have barriers to entry- it used to be a capital crime to claim you were an MD.

There's two ways to see this issue. From the perspective of the employer, an academic credential acts as a 'seal of approval'. There is an assumption made of the level of ability/knowledge/etc, which underscores the importance of the job interview.

From the perspective of the student (or 'client'), there is the assumption that 'you get what you pay for'. Twofish-quant very forcefully (and correctly) points out how this is potentially a very unfair deal for the client- because there is no clear correlation between cost/prestige and educational benefit.

Much better to have a clear idea of what one pays for, by paying tuition. This is the siren call of for-profit universities- explicit claims that one can qualify for a better job by paying for a credential issued by (for example) U. of Phoenix.

 

[Ryker]

I'm not denying that many jobs have barriers to entry- it used to be a capital crime to claim you were an MD.

There's two ways to see this issue. From the perspective of the employer, an academic credential acts as a 'seal of approval'. There is an assumption made of the level of ability/knowledge/etc, which underscores the importance of the job interview.

From the perspective of the student (or 'client'), there is the assumption that 'you get what you pay for'. Twofish-quant very forcefully (and correctly) points out how this is potentially a very unfair deal for the client- because there is no clear correlation between cost/prestige and educational benefit.

Much better to have a clear idea of what one pays for, by paying tuition. This is the siren call of for-profit universities- explicit claims that one can qualify for a better job by paying for a credential issued by (for example) U. of Phoenix.

Yup, it's all economics - http://en.wikipedia.org/wiki/Signalling_(economics).

 

[NeedsHelp1212]

LOL physics has not gotten any easier, i simply hate it. Since making this thread by grade has stayed at an 84 thanks to good lab grades. I try so hard on my labs just to get A's on them but since i posted here i got a 30/50 on the projectile motion test ( i ran out of time on the last question and knew how to answer it..could of got a 40!) then for number 1 i messed up fricking adding and def could of got around a 45). Then on my last test i made another stupid mistake and got a 73/100. I knew how to do all the problems aside from 1, but since i messed up on 2 it completely screwed me. Open ended questions in science are the doom of me. I have a quiz this week plus a couple of labs so i can raise my grade near a B+ if i do well. Then with the extra credit project i might with a miracle make it to an A. So not sure why i posted here, guess just to validate that physics is indeed very hard. By the way right now we working on work, kinetic energy, and the work-kinetic energy theorem. I just spent the past hour studying and i completely get it but watch me the fail the quiz!

 

[Chunkysalsa]

Are you in high school or college? All that time between posts and you guys are only on work/energy, seems kinda slow. Which is normal for high school ^_^.


I'm taking physics right now as well (college), I don't find it hard in the sense that is difficult to grasp. It's just very, very time consuming. I currently have a B in lecture and an A in lab and the class avg on tests is around the low 50s (and dropping with every tests). I can't wait till drop date passes next week, there's going to be like 10 people max. Too bad my two friends won't finish with me v_v.

We just tested on rotational physics with fluid dynamics being next.

 

[planck42]

Open-ended questions in science are the doom of you? What kind of open-ended questions?

 

[CheckMate]

Not to be mean or anything but Math or physics or other sciences aren't for everyone. Not everybody can be doctors, engineers, physicists, etc... Society needs some people doing this and other that... Maybe it's not for you?

 

[quantumdude]

 

[Shackleford]

Well, physics is "easy," but the math required to do some physics problems is quite hard. In other words, solving particular problems involves solving very complicated mathematical equations.

 

[NeedsHelp1212]

Are you in high school or college? All that time between posts and you guys are only on work/energy, seems kinda slow. Which is normal for high school ^_^.


I'm taking physics right now as well (college), I don't find it hard in the sense that is difficult to grasp. It's just very, very time consuming. I currently have a B in lecture and an A in lab and the class avg on tests is around the low 50s (and dropping with every tests). I can't wait till drop date passes next week, there's going to be like 10 people max. Too bad my two friends won't finish with me v_v.

We just tested on rotational physics with fluid dynamics being next.

high school, and i think we are going REALLY fast. We are already threw 200 pages in the book and its not like I just have 1 subject to worry about. I have 3 tests tomorrow, ap history, pre-calc, and physics

 

[Klockan3]

Well, physics is "easy," but the math required to do some physics problems is quite hard. In other words, solving particular problems involves solving very complicated mathematical equations.

When doing physics problems the maths is physics, if you don't understand that maths then you don't understand the physics.

 

[Shackleford]

When doing physics problems the maths is physics, if you don't understand that maths then you don't understand the physics.

Mathematics is entirely arbitrary. It does not dictate physical phenomena. However, it's used by physicists as a language to describe physical phenomena quantitatively very precisely. Someone can understand Newton's Laws qualitatively but not be able to express it quantitatively. That's my distinction - a very fine one, I know.

 

[theJorge551]

I am not sure where to post this thread but i guess here. So not to brag but I have gotten straight A's most of my entire life, I found school pretty easy aside from some spots (like Spanish). My GPA is very high and I am ranked in the top 2 percent of my class. So once I completed spanish 3 i felt i wanted to drop it and place an extra science in. So i took physics thinking it would be easy. Well it's far from that, i have an 88 half way through the marking period and probably just failed the quiz today bringing my grade to like an 83-85. I don't know why the subject seems so hard. The problem is I have a lab due Wed and I am not sure what to write. I have to try to get a B+ this marking period so my GPA does not drop. Does anyone have any advice on how to do good in physics? Right now we are going over projectile motion at an angle. One dimensional motion was pretty easy, second dimensional motion was easy until we got to the point where you had to split the vectors up into components, and now we are starting this. So pretty much my question is, how can i improve in physics?

Based on how you characterize the class, it seems to be your first physics class. I can guarantee you with full honesty that if you stick it out, the material will "click" and your grades will improve. It goes without saying that, at least in my experience, that an introductory physics course is meant to seem extremely more difficult than it has to (mainly to weed out the non-science minded students, in my opinion.) When I took my first physics course last year (it seems to be similar to yours), I was getting low 80's; the class average for our first kinematics test was a 45%. Before mid-terms came around, I doubt there were more than one or two students who got less than 90% on every homework assignment, test, and lab. It is true, they are very intelligent - but even those just taking the class to get it out of the way were doing well at some point. If you persist and get rid of your previous conviction - the mindset that you're going to get high 90's in every class - you'll certainly improve.

 

[General_Sax]

Mathematics is entirely arbitrary. It does not dictate physical phenomena. However, it's used by physicists as a language to describe physical phenomena quantitatively very precisely. Someone can understand Newton's Laws qualitatively but not be able to express it quantitatively. That's my distinction - a very fine one, I know.

So, F=ma (a straight line provided that mass is constant) is more difficult to "understand" than it's implications. That's rich, because I'm not even sure what the implications of such a statement is (F=ma), but I (and basically any 14 year old) could solve for any variable 7 days from Sunday.

 

[NeedsHelp1212]

So, F=ma (a straight line provided that mass is constant) is more difficult to "understand" than it's implications. That's rich, because I'm not even sure what the implications of such a statement is (F=ma), but I (and basically any 14 year old) could solve for any variable 7 days from Sunday.

Exactly, I have no problem solving for a variable. Too bad the problems don't simply give you the numbers needed to plug into the equation.

 

[NeedsHelp1212]

Based on how you characterize the class, it seems to be your first physics class. I can guarantee you with full honesty that if you stick it out, the material will "click" and your grades will improve. It goes without saying that, at least in my experience, that an introductory physics course is meant to seem extremely more difficult than it has to (mainly to weed out the non-science minded students, in my opinion.) When I took my first physics course last year (it seems to be similar to yours), I was getting low 80's; the class average for our first kinematics test was a 45%. Before mid-terms came around, I doubt there were more than one or two students who got less than 90% on every homework assignment, test, and lab. It is true, they are very intelligent - but even those just taking the class to get it out of the way were doing well at some point. If you persist and get rid of your previous conviction - the mindset that you're going to get high 90's in every class - you'll certainly improve.

thanks for the confidence. I definitely need it ( and I do better when I have confidence)