Another gravity question

Discussion in 'Physics & Math' started by Adam, Jun 12, 2002.

  1. Adam §Þ@ç€ MØnk€¥ Registered Senior Member

    Messages:
    7,415
    Basically, do gravitational forces from different massive objects combine?

    A star ahs a certain amount of gravity. But as I understand it, a galaxy has stronger gravity that justt he maximum individual component.

    Let the lines below indicate the strength of gravity wells.

    Star:
    *------>

    Two stars:
    *------>
    *------>

    Galaxy:
    *------------------------------------------------------------------>

    See what I'm asking? How exactly is the gravity well of a galaxy stronger than the strongest component? Or isn't it stronger at all?
     
  2. Google AdSense Guest Advertisement



    to hide all adverts.
  3. James R Just this guy, you know? Staff Member

    Messages:
    39,421
    Gravitational forces add together. The gravitational pull of a galaxy is equal to the sum of the the gravitational pulls of all the stars in the galaxy.
     
  4. Google AdSense Guest Advertisement



    to hide all adverts.
  5. ~The_Chosen~ Registered Senior Member

    Messages:
    1,047
    Buy those thick College Physics textbook by Giancoli (latest edition), it's a very good book for conceptualizing and learning about the basics of physics.

    There are good problems on that site. I suggest you buy the book and run through anything you don't know. Or just take a course

    Please Register or Log in to view the hidden image!

     
  6. Google AdSense Guest Advertisement



    to hide all adverts.
  7. Adam §Þ@ç€ MØnk€¥ Registered Senior Member

    Messages:
    7,415
    Thanks. I assumed gravitational forces add together, since that whole mass thing n all. But how? Is the way it happens understood at all?
     
  8. James R Just this guy, you know? Staff Member

    Messages:
    39,421
    Yes, it's well understood.

    Every bit of matter in the universe attracts every other bit of matter, with a force which is proportional to the product of the masses and inversely proportional to the square of the distance between the bits. (Sir Isaac Newton)
     
  9. Adam §Þ@ç€ MØnk€¥ Registered Senior Member

    Messages:
    7,415
    I'm ok with all that. But how do the forces of gravity from different masses combine? With charge, for example, we're talking about simple balance between positive and negative. The same concept applies for up and down, spin, et cetera. What's going on with the combination of gravity forces? Is it, again, balance or equilibrium like we see in the other forces? If so, how? What is the mechanism involved? Can you explain the mechanism in a way similar to how we explain charge and spin and such?
     
  10. James R Just this guy, you know? Staff Member

    Messages:
    39,421
    Gravitational forces are vectors (just like every other force).

    To find the net gravitational force on an object, we add up the gravitational force vectors from all the masses attracting the object. In the addition process, we must take into account not only the magnitudes of the forces, but also their directions (i.e. we do a vector addition).
     
  11. Xev Registered Senior Member

    Messages:
    10,943
    Adamski:
    Gravity is the "warping" of spacetime that an object causes. This "warping" gives rise to force, and this force "pulls" on another object. When there are more masses, the "warping" is more extreme and thus stronger.
     
  12. Adam §Þ@ç€ MØnk€¥ Registered Senior Member

    Messages:
    7,415
    Grrr. What I am after is the mechanism for how it happens. Like with otehr thigns we have gluons and colour bonds or whatever. What is the method by which gravity/mass combines?
     
  13. James R Just this guy, you know? Staff Member

    Messages:
    39,421
    Not sure what you're after, exactly.

    Perhaps gravitons (if they exist). Perhaps the gravitational field.

    ????
     
  14. Adam §Þ@ç€ MØnk€¥ Registered Senior Member

    Messages:
    7,415
    Okay, I've been looking at gravitons on the web. Yep, that's what I'm after. Something that isn't known to exist. That sucks.
     
  15. ~The_Chosen~ Registered Senior Member

    Messages:
    1,047
    Perhaps Thed may answer this, I am learning more about the Big Bang and more about the Plasma Theory.

    But the Big Bang hypothesizes that there is another dimension. Time is the 4th dimension, and a 5th dimension contains a super massive object known as a Higgs Boson which exists in subnuclear dimensions. The Higgs Boson and mass in our dimension interact with one another to cause gravity. Gravity is most likely an interaction of energy.

    They need this to exist to support the Big Bang Theory.

    Try some of these interesting links.

    What exactly is the Higgs boson? Have physicists proved that it really exists?

    How does the Higgs boson affect string theory?

    One Step Closer to the God Particle

    Big Bang's Non-inflatable Dimensions

    Also, you should get Giancoli's Physics book, it explains basically everything you need about Physics in general, to work, force, thermadynamics, and so on. It has nice diagrams, the problems show you mathematically how it all fits and it's 1000+ pages.

    Please Register or Log in to view the hidden image!

     
  16. overdoze human Registered Senior Member

    Messages:
    310
    Hi Adam,

    I understand the need to categorize and classify, but is that really enough? Like, we have "photons". Yes, it has a name, but what is it?

    A particle and a wave, say some. But that's ridiculous; the two concepts are logically incompatible. Which in reality means that it isn't both -- it's neither! So, sometimes it manifests itself as a wave, sometimes as a particle -- but what is it really? Aside from a name, nobody knows...

    Some say it's an "energy packet". Whoopty-doo, but what the heck is "energy" then? Ability to do work? What's that, a packet of ability to do work? That sometimes acts like a wave and sometimes like a particle? Bleh...

    Nah, all we're doing is playing games. Giving names to things doesn't help any when what we really want is to understand the thing behind the name.

    So... "gravitons". "Gravitational waves". "Space-time". It's all bullshit. What is space? A Cartesian coordinate system? Or is that just another name?
     
  17. TruthSeeker Fancy Virtual Reality Monkey Valued Senior Member

    Messages:
    15,162
    Adam,

    I think I know what you are talking about...
    Imagine a blanket held straight in the air. If you put balls on it, the blanket will bend to accomodate the balls. Depending on the weight, the mass of the ball, it will bend a lot or not.

    If you are talking in the sobatomic level, I guess there's no gravity. In the subatomic level there are other forces, but no gravity. Gravity only makes difference in the macrocosmic world. However, if gravitons exists, I believe gravity is the strongest force in the universe... instead of the strong nuclear force...

    If gravitons exist they are probably quarks and it will be pretty hard to detact them...
     
  18. TruthSeeker Fancy Virtual Reality Monkey Valued Senior Member

    Messages:
    15,162
    overdoze,

    I like that...

    Please Register or Log in to view the hidden image!


    Did you ever learn Taoism?

    Please Register or Log in to view the hidden image!

     
  19. TruthSeeker Fancy Virtual Reality Monkey Valued Senior Member

    Messages:
    15,162
    overdoze,

    I like that...

    Please Register or Log in to view the hidden image!


    Did you ever learn Taoism?

    Please Register or Log in to view the hidden image!



    You made me remember that I would post about this subject... thanks...

    Please Register or Log in to view the hidden image!

    Please Register or Log in to view the hidden image!

     
  20. Xev Registered Senior Member

    Messages:
    10,943
    *Xev quietly thanks Cthulhu for the vodka, or else this would be impossible*

    Nelson, kindly keep your pseudoscience out of physics and math.

    It is a very, very weak force but it exists.

    Strongest force? What are you talking about?

    Umm, Nelson dear, gravitons and quarks are different things.

    Chosen:
    Giancoli is indeed an excellent textbook for beginning physics! I have his fifth edition sitting right next to me.

    However...

    No, the Higgs is not necessary to support the big bang theory - it is presumed to be necessary to complete the standard model.

    Simular things, but different.

    Also, the Higgs need not be outside our current four (well, actually 11 or 24 - but we won't get into Kaluza-Klein) dimensions.

    As for gravity being an interaction of energy, you're right. Remember that E=mc^2, and that mass rather "causes" the gravitational force.

    Nice post. If you ever want a beginning paper on the Higgs, I've got one from a few semesters ago.

    Adam: Gravitons. Yep, we have yet to detect such. According to the standard model, they should exist.....absence of evidence is not evidence of absence, of course, but I do wonder how this affects the validity of the SM.

    But my explanation - does it not work? Could you clarify the question?
     
  21. TruthSeeker Fancy Virtual Reality Monkey Valued Senior Member

    Messages:
    15,162
    Xev,

    ...?
    Which pseudoscience...?

    Do you really concider... let's say... 0,00000000000001 of force...?:bugeye:

    I think I made myself sufficiently clear...

    Gravitons are types of quark...
    Have you ever study this...?

    Please Register or Log in to view the hidden image!

     
  22. Xev Registered Senior Member

    Messages:
    10,943
    Nelson:
    Daoism. I do not think this is the appropriate forum for it.

    .0000000001 of what force? Gravity?

    Yes, it's a bloody force! It is a very weak force sub-atomically.

    There IS NO STRONGEST FORCE! They all apply over different levels.

    They are a hypothetical type of sub-atomic particle. Not a type of quark.
    Quarks:
    http://www2.slac.stanford.edu/vvc/theory/quarks.html
    Here, this should help:
    Gravitons:
    http://research.spinweb.com/glossary/terms/gravitons.htm


    Well, let's see, I've only studied informally for four years, and I've only studied physics at college level for four semesters......

    Looks like you do indeed have somthing to be embarassed about.

    Please Register or Log in to view the hidden image!



    Now Nelson, if your ego can't stand being corrected on science, I'd advise you to stick to religion and parapsychology. I'm being as gentle about this as I can, but I do not appreciate having my credentials questioned simply because you cannot stand being wrong.

    We're all wrong at times, Nelson. The best thing to do is to accept it with dignity and grace and try to learn.
     
  23. TruthSeeker Fancy Virtual Reality Monkey Valued Senior Member

    Messages:
    15,162
    Xev,

    I was just comparing what overdoze said with Taoism...

    That's what I'm talikng about...

    Only because they apply to different levels it doesn't mean we can't compare them...:bugeye:

    Ok... then...
    BURN THE BOOKS I READ!!!!!

    Please Register or Log in to view the hidden image!


    Please Register or Log in to view the hidden image!

    Please Register or Log in to view the hidden image!

    Please Register or Log in to view the hidden image!

    Please Register or Log in to view the hidden image!

    Please Register or Log in to view the hidden image!



    Ok... then all the books I read on the subject are wrong and MUST be burnt...:bugeye:

    Please Register or Log in to view the hidden image!

     

Share This Page