What Should You Study First in Physics at 18?

[Tohz]

Hello, I'm getting done with the high school (I'm 18 years old btw) I've failed many years... sort of motivation problem... What I'm going to ask might sounds a bit confused but I really what to start "somewhere". Right know, I've got some Physics and chemistry courses at school (Nuclear, Electricity, Ions) and I'd like to start learning more. The problem is... about what should I start reading? Physic really interest me. So please if you have any advices to give me, i'd be glad to hear them. :)

 

[arildno]

Here's the short version:
Maths, especially calculus.

 

[Tohz]

What do you mean by calculus?

 

[TheDude710]

I would stay start with mechanics, then E and M, then modern physics. You should leave some calculus. If you want to jump into something really interesting that you might beable to grasp right now, read about special relativity.

 

[Tohz]

E and M stand for ?

 

[renta]

my guess is "electronics and magnetism". that's what i had to take when i was a physics major

 

[rocketcity]

Why do all of the 'popular' physics texts (i.e., non-textbooks meant to be read by the masses) eschew equations? I picked one up that had an interesting title, saw on the back that it had a cartoon of a chalkboard with a professor happily writing NO EQUATIONS, and promptly put it down. This seems akin to proudly blurbing "ENTIRE BOOK WITHOUT VERBS!"

I love Feynman, but I don't think I can recommend his lectures to an aspiring physicist. But besides him, most of the popular guys are writing about quantum, relativity, or (even worse), their own theories with which they hope to supplant one or the other or both. Asimov wrote some okay stuff, but I never cared that much for it. Maybe I never read the right Asimov text.

I think the best way to learn physics is to get together with one or two friends and dissect a good introductory text--say, Serway or Halliday and Resnick (type their names and 'Physics' into amazon.com or half.com. For ten or twenty bucks, you can get an old edition (this stuff doesn't change very quickly)) and pick through it together. Lots of neat pictures, one or four chapters on every topic in physics, which will contain a lot more useful information than the popular stuff you could buy at a brick-and-mortar Barnes and Noble, and thousands of questions to work through. If you can't find some friends to do it with, do it with us; we'll help you.

 

[selfAdjoint]

There is a saying in the book business: Each equation in a book cuts the the buyer numbers in half. Authors are pressured to translate their equations into words. Kaku and Greene are celebrated for doing this as well as anyone can, but I agree it is a loss. There is a big hole in the book market between stuff aimed at non quantitative folks and graduate level textbooks.

 

[Gokul43201]

Three words : RESNICK AND HALLIDAY

(I've heard Giancoli is popular too)

 

[rocketcity]

You can get a new Halliday and Resnick for something like $140 bucks--or you can buy a 2000 edition for $0.75 on half.com. (Undergraduate texts are generally devalued to Sears and Roebuck catalog status as soon as the professors switch to a newer edition.)

I've heard that saying, selfAdjoint, and although I understand the sentiment, I can't help but feel frustration at the result of such an attitude.

The first book I grabbed, good ol' Griffiths-of-the-two-cats, has 1,144 numbered equations. If only Griffiths had known the rule of two, he could have sold 10^344 times as many copies. Rather than selling the (say) 100,000 he sold, he could have sold 10^349 copies. He could have printed one copy on every nucleon in the sun and sold 10^275 suns worth of them for every second of the entire history of the universe! He could have encoded his book in the quantum states of individual electrons, and the combined mass of those electrons would exceed the mass of the observable universe!

If we embrace physics texts with no equations, then we are damned to live in a world where publishers can say stuff like 'every equation cuts your sales in half' with a straight face.

 

[selfAdjoint]

The is a gap between, say, having passed a calculus course with a good grade and having enough math under your belt to really profit by a quantum field text. One of the non-existent courses/books needed is "A 1001 things a clever analyst can do with an integral". You notice that in the biogrqphies of Feynmann, that is what he taught himself (differentialtion under the integral sign), and his mastery of that specialized kind of calculation was one of his strong points throughout his career. Alas, since his time the field has proliferated. He contributed new tricks himself and so did the generation of physicists of the 1950s and 1960s. I'm just talking about QFT here; String physics is a whole nother world.

Most physics grad students learn a lot of this by having their noses held to the grindstone in their first year intro courses. But it's pyschologically impossible for all but a miniscule proportion of wannabes to do that to themselves. So if someone could write a short text on "From Calculus 102 to QFT Math" it would open up the QFT graduate textbooks to a wider readership.

 

[russ_watters]

The is a gap between, say, having passed a calculus course with a good grade and having enough math under your belt to really profit by a quantum field text.

And then there is the poster of the thread, who apparently has never even heard of calculus...

I think you guys are way ahead of what he's looking for. He's probably never even had basic Newtonian physics and that's where one needs to start (along-side with calculus).

 

[Artman]

A good place for this poster to start is with a course based on the book "Conceptual Physics" by Paul G. Hewitt. This is the type of textbook without too many equations, nothing worse than a little algebra. From there he can discover what interests him and decide if it is worth the effort of learning the advanced math required to do further study. It may be a little simplistic, but like Russ pointed out, Tohz said he doesn't even know what Calculus is.

http://www.conceptualphysics.com/books.shtml