Why is Physics So Hard? Advice to Improve

[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)

 

[General_Sax]

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.

Good. They can't make it too easy.

 

[theJorge551]

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

We all do, man. Glad to know I could help, and keep us posted!

 

[Klockan3]

Mathematics is entirely arbitrary.

No it is not, it was constructed to fit the laws of this world.

It does not dictate physical phenomena.

No, but it was created in such a way that it is optimal for expressing physical phenomena and it is our only way to do so.

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.

Then I'd say that he most likely don't understand it qualitatively, he just think that they does. People have so many erroneous beliefs about things like physics, it takes a really long time to hammer them out and it is impossible to do that without the maths, words like acceleration and velocity have different meaning to different persons till you define it mathematically etc. I'd say that it is really rare for people to understand Newton's Laws qualitatively but it is really common to be able to express it quantitatively. People in general are a lot better at maths than they are at physics.

Also, no your view is far from delicate, I have the same opinion but got to the reverse conclusion. When learning the physics you either already know the maths or you do learn the maths implicitly in the process. If you take a non calculus based physics course you should after that understand enough concepts from calculus that you could take your first calculus course in a week or else you didn't understand the physics. Calculus is trivial once you understand concepts like F=ma qualitatively.

 

[chiro]

No it is not, it was constructed to fit the laws of this world.

No, but it was created in such a way that it is optimal for expressing physical phenomena and it is our only way to do so.

Then I'd say that he most likely don't understand it qualitatively, he just think that they does. People have so many erroneous beliefs about things like physics, it takes a really long time to hammer them out and it is impossible to do that without the maths, words like acceleration and velocity have different meaning to different persons till you define it mathematically etc. I'd say that it is really rare for people to understand Newton's Laws qualitatively but it is really common to be able to express it quantitatively. People in general are a lot better at maths than they are at physics.

Also, no your view is far from delicate, I have the same opinion but got to the reverse conclusion.

Definitely agree on this comment.

One of the things mathematics is good at is if used correctly, it provides a good way to state the structure and behavior of particular things which include physical systems.

Because of this non-ambiguity it is usually a good way to really get all people to have a standardized interpretation and understanding of the so called physical systems. Not only that, because of the non-ambiguity it allows anyone to compare the reality of the system against the language of the theory and straight away anyone can tell if its outright wrong (whether in general or by a single anomaly) or whether it still stands against the specific tested situation.

On why physics is hard, one thing I have to add is to first think about the history of physics (this can very well apply to any science humankind has endeavored in building).

Our understanding of physics has come about by a very large number of people who are very smart and very dedicated through curious investigation to find out about their world. I think everyone has at least one curiosity about their world, but with physics it is certainly something that needs a fair amount of dedication, insight, and possibly some luck to raise the bar on understanding our universe.

Over time as things have become more well understood, other people have found ways to take and transform that into semester or year long courses that provide a very well condensed, concise, and engineered view of something that otherwise took hundreds of years to understand and develop.

With this said, it is not surprising that many people simply do not understand or "get it" straight away. When we taught the engineered, refined material we are very likely in our time as a student come across situations where we can't look at the material in a variety of perspectives (Feynman referred to this as 'Fragile Knowledge'). It usually takes someone that has been doing it for a decade or longer to know all of the intricacies of their subject which are often in some form at least, left out of curriculum.

So don't feel bad if you don't get it all straight away. Most people don't and even those who do go well in their coursework may find out later that their understanding was not as dense as they thought when they gain new insights, perspectives, and relationships in their working knowledge: most of us do when working on something for significant lengths of time.

 

[thrill3rnit3]

Have some orange juice:

http://www.youtube.com/watch?v=HKTSaezB4p8&feature=related

 

[sentient 6]

because is physics was easy... then it just wouldn't be fun anymore...

 

[NeedsHelp1212]

I seriously think i got a 100 on the quiz today! lol so happy

 

[Shackleford]

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.

I think you're misunderstanding me. It's a description of physical phenomena.

When I do this thing to various other things, they move.

That's probably the most general and ambiguous qualitative understanding of Newton's Laws.

Expressing it a little better:

When I perform some action on an object, it acquires motion. Through experimentation, this motion depends on the "magnitude" of the action, the "size" of the object, etc.

That's a little more lucid. Still, the definitions of those terms are interrelated. That's why my quantum professor says such things when explaining some physics concepts, "The physics is easy. Unfortunately, we have to do deal with the mathematics."

All I'm saying is the very complicated mathematics used to very precisely describe physical phenomena can be vastly more difficult than merely understanding what happens at a qualitative level.

 

[theJorge551]

Have some orange juice:

http://www.youtube.com/watch?v=HKTSaezB4p8&feature=related

Thanks...that made my week.



...and yes, I am going now to get some orange juice.

 

[NeedsHelp1212]

We all do, man. Glad to know I could help, and keep us posted!

to keep everyone posted on my journey through high school physics i got an A- for the first marking period! Too bad i did bad on my first quiz for the 2nd MP so I am in for another uphill climb. I have a big test tomorrow on momentum and collisions. It's extremely easy so I am confident i can get a good grade. Too bad I have 4 tests tomorrow as well ( why do teachers all give tests on the same day..lol)