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Is it possible to hate Newtons Laws?

  1. Jun 15, 2008 #1
    Is it possible to hate Newtons Laws???


    I am taking a course in physics, and I have noticed that Newtons Laws, and Newtons Mechanics just bores me to death whenever I am reading about it or trying to do questions.

    On the other hand, we started to do some Energy and Work chapters, and the theorems and I just love this stuff. It might be the fact that I tend to find these topics more chemistry related than Newtons Laws. I was wondering if this was weird to hear from someone, and if it was a bad trait to have or if there are others like me?
  2. jcsd
  3. Jun 15, 2008 #2
    It's possible; in fact the majority of physics students seem to.

    It is, however, irrational. What did Newton's laws ever do to you? They are nothing but a descriptive model of the workings of nature.
  4. Jun 15, 2008 #3
    I think the reason I tend to find more advanced Physics topics is that generally I see the macro world around me all the time. It just does not interest me as much anymore as does the nano-world and its characteristics and Laws of Nature do.

    Not sure if this is how others feel, but this is generally I think why I tend to feel bored with Newtonian Mechanics.
  5. Jun 15, 2008 #4
    the introduction to any subject is never anything mindblowing. I'm sure the unit conversion chapter of chemistry didn't captivate your attention either
  6. Jun 15, 2008 #5
    There was this one time that they made me trip, then fall, then absorb a large quantity of force - causing me to have a broken bone.

    Actually, I'm pretty sure those bastards are responsible for every broken bone I had as a kid. And stubbed toe. And everything I've ever dropped on my foot. Not to mention stuff like scraped knees.
  7. Jun 15, 2008 #6
    I think you are bored because it is basic physics. Do you understand that Newton's second law is a differential equation?

    The problems involving constant forces pulling blocks etc were boring for me as well, but that just made me read ahead.
  8. Jun 15, 2008 #7


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    I think I went through a period of hating Newton's Laws after learning the Lagrangian/Hamiltonian formalization of Classical Mechanics and realizing that Newton's laws were all for nothing.
  9. Jun 15, 2008 #8
    No doubt that it was a boring chapter, but that is all it was - and sometimes only a section of a chapter. But I am talking about almost 1/5th of a textbook.

    Yes I am actually taking calculus based Physics, so I am aware that F=ma is a differential equation.
  10. Jun 15, 2008 #9
    I used to find newton's laws, and indeed most of basic physics to be pretty boring. Surprisingly, the 3rd time I learned basic physics (in college, after taking physics and AP physics in high school) I found it very interesting. The one thing that made a "switch" flip in my mind from uninteresting to interesting was when I had to do a problem where you figured out the acceleration of a car based off of the angle of a pair of foam dice hanging from a mirror :D I thought that was a really interesting problem.
  11. Jun 16, 2008 #10
    Yup. Classical mechanics taught from the Lagrangian/Hamiltonian point of view is so much more useful than Newtonian mechanics.
  12. Jun 16, 2008 #11
    But there's a reason that the Lagrangian and Hamiltonian formalisms are useful. All of that standing on the shoulders of giants nonsense.
  13. Jun 16, 2008 #12
    i know, seriously.
  14. Jun 16, 2008 #13
    I'm confused. Aren't the work and energy theorems part of Newtonian Mechanics? For example conservation of mechanical energy relies on the definition of force from Newton's Second Law. Anyway, maybe the problem is your perspective: realize that the laws of mechanics (conservation of momentum, energy, and Newton's Laws) are all different routes to get to a final result. Some methods are easier than others for example using momentum and energy for collisions or Newton's Laws for oscillations.
    Last edited: Jun 16, 2008
  15. Jul 23, 2008 #14
    Re: Is it possible to hate Newtons Laws???

    You are making Newton spin with an enormous angular velocity in his grave. I agree that Lagrangian Mechanics is easier to work with when you have practiced it a certain amount of time. But it is (T-V) {the Newtonian One} obeying the Euler equation which gives you that comfort.

    Lagrangian Mechanics is only a formulation, its essence is in Newtonian Mechanics. Classical Mechanics is still = Newton. And what is all that thing about masses and pulleys, should we expect to solve the hydrogen atom before solving those boring accelerating masses tied together.

    Actually masses tied together with strings are just as boring as the hydrogen atom, or QED. It is all about understanding nature, none is more different than the other. If one is boring all is boring, if one is fun all is fun.

    But I cannot restrain myself from saying this:

    Reaching the end of a calculation and then simplifying the end result by enormous algebra work which takes even more time than reaching the end result is BORING.
  16. Jul 23, 2008 #15
    Re: Is it possible to hate Newtons Laws???

    while bookkeeping isn't as fun as solving the mysteries of nature, I contend that simplifying a calculation to a concise, physically meaningful result is, to me, more satisfying than performing the calculation itself.
  17. Jul 23, 2008 #16

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    Re: Is it possible to hate Newtons Laws???

    There are many real-world cases where the Lagrangian/Hamiltonian point of view is literally worthless. Most real-world problems involve non-conservative forces for which no potential (or even generalized potential) exists.
  18. Jul 24, 2008 #17
    Re: Is it possible to hate Newtons Laws???

    My first year classical mechanics lecturer said he found most of the course boring.
    The thing that I think is really at the heart of the matter is that most classical mechanics seems to be true by definition: velocity is the rate of change of position with respect to time, a force is something that causes acceleration, etc. And why, in any event, do we CARE how fast two cars recoil from a collision?
    But when you study say quantum mechanics or EM, then it's different. The kind of differential equations that seem almost trivial and dull when couched in terms of newtonian physics suddenly give you insight into a world you can't picture so easily. The concepts themselves are hard to understand, rather than just the homework problems. Simple chemistry is perhaps more intresting than simple physics because it tells you something you didn't already intuitively feel, that gives you insight into the world around you; I suspect the reason you find problems couched in terms of energy more interesting is that they feel more insightful somehow. One reason I think lots of people like lagrangian or hamiltonian dynamics is that the elegant formulation makes you look at things in a new way. For example, the fact that a particle "sniffs out" the path of least action before it starts moving really rams home the determinism of QM.
  19. Jul 24, 2008 #18
    Re: Is it possible to hate Newtons Laws???

    Ah, don't worry about hating Newton's Laws. Getting into my second year of grad school in physics, I've started hating them too. I think the reason for this is that it's not real physics. Real physicists don't do problems with blocks on inclines or balls on a pendulum. Real physicists probe the inner structure of nuclei, study acceleration mechanisms in astronomical sources, and do other cool stuff. When was the last time anyone published a paper on finding the force on some crossbeam on a bridge? We've got engineers to do that stuff for us, and they're probably a lot better at it than we are. Sure, basic mechanics, optics, etc., are a necessity for those who want to do physics. Before you can study quantum mechanics, which is the basis for most active fields of physics, you need to understand Newtonian concepts like momentum, angular momentum, potential energy, and even harmonic oscillators. But if Newton's Laws were all that there was to physics, I'd have left a long time ago.
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