Lars Posted June 17, 2006 Share Posted June 17, 2006 Im not too sure how to word this so hang with me Well, my year. 8 science teacher is not the brightest bulb in the box, but he absouloutly stumped me with a question today; "Why is gravity there?". Is there even an answer for this? If I dont get a good answer by monday I have a lunch time clean up (long story). Am I crazy or is that an impossible task to set (especially for an 8th grader). Link to comment Share on other sites More sharing options...
swansont Posted June 17, 2006 Share Posted June 17, 2006 From a Newtonian perspective, it's caused by mass (The general relativity explanation is more complicated). But why mass causes gravity isn't something that has been answered, AFAIK. We just know that it does. Link to comment Share on other sites More sharing options...
the tree Posted June 17, 2006 Share Posted June 17, 2006 An awnser (not the awnser, because no-one is anywhere near sure) involves one hell of a stupid word: gravitons which as far as I understand is held by the "strong force" (another insanely stupid word, QM is full of them) around particles that have mass and subsequently bring others in. Or at least that is one model. At most peoples level, even that of a physics teacher, it's fairly easy to say that things that have mass just do exert a on, other things (that don't have to have mass themselves, this confuses me as well). Anotherother fun questions that a lot of teachers wont the awnsers to is: "If I shake this string then I get a wave of string but, what is light a wave of?", the awnser is that it isn't. Which really amuses me for some reason. Link to comment Share on other sites More sharing options...
cpwmatthews Posted June 17, 2006 Share Posted June 17, 2006 What if gravity was not a downward pull but a downward force? Say that particles from our atmosphere are attracted to the centre of the earth and exert some downward motion, crazy maybe, Link to comment Share on other sites More sharing options...
Lars Posted June 17, 2006 Author Share Posted June 17, 2006 That is what I was thinking last night, But where does the force come from? Gravity is stupid Link to comment Share on other sites More sharing options...
cpwmatthews Posted June 18, 2006 Share Posted June 18, 2006 There are particles, and you must forgive my idiousy, that are constantly falling on our planet, the hell if I can remember the name, Nutrinos?? Any way what we do know about gravity is that it acts all around the earth but do we know if gravity exerts the same force at every point around the earth i.e. north south e.t.c.? We know gravity is less in space so from that we can concur that our atmosphere also plays a part in increasing it's effects. but the one fact that is obvious is that it is always connected to the centre of what ever planet you are on, what do you think? Link to comment Share on other sites More sharing options...
the tree Posted June 19, 2006 Share Posted June 19, 2006 What if gravity was not a downward pull but a downward force?Ignoring the "downward" thing, gravity is a force.Say that particles from our atmosphere are attracted to the centre of the earth and exert some downward motionWhat makes you think they aren't/don't? Why wouldn't they?But where does the force come from?You want something more precise than "from gravitons"?Gravity is stupidWithout gravity, there'd be much less to prevent the increase of energy and the universe would be drawn to it's heat-death much sooner. Basically, the whole would just be damn boring. We wouldn't even have stars.Any way what we do know about gravity is that it acts all around the earthWe know an awful lot more than that.but do we know if gravity exerts the same force at every point around the earth i.e. north south e.t.c.? No it doesn't.We know gravity is less in space so from that we can concur that our atmosphere also plays a part in increasing it's effects.WHAT THE HELL?!?!? Where oh where is your logic there? Our atmostphere is prone to exactly the same rules as all other matter and there is no reason why it shouldn't be.but the one fact that is obvious is that it is always connected to the centre of what ever planet you are on, what do you think?That gravity isn't, and never was confined to planets? Link to comment Share on other sites More sharing options...
ajb Posted June 23, 2006 Share Posted June 23, 2006 Physics cannot put and answer to "why", but tells you "how". Gravity is observed in nature, falling apples, the motion of planets etc.. What coures gravity is mass/energy. It plays the same role as electric charge does in electrostatics. If things have no net charge then their is no electric force between them. The same is true of gravity, no mass or energy then no gravitational force. Or are you really asking "why gravity is not just electromagnetic in nature"? Link to comment Share on other sites More sharing options...
bascule Posted June 23, 2006 Share Posted June 23, 2006 That is what I was thinking last night, But where does the force come from? Gravity is stupid The answer in general relativity is that objects with mass bend/warp the space around them, causing nearby objects to be attracted to them. Link to comment Share on other sites More sharing options...
KaiduOrkhon Posted July 17, 2006 Share Posted July 17, 2006 Im not too sure how to word this so hang with me Well' date=' my year. 8 science teacher is not the brightest bulb in the box, but he absouloutly stumped me with a question today; "Why is gravity there?". Is there even an answer for this? If I dont get a good answer by monday I have a lunch time clean up (long story). Am I crazy or is that an impossible task to set (especially for an 8th grader). [/quote'] Perhaps you've answered your science teacher's doubletalking question best in commenting that he's not the brightest bulb in the box. His question translates to the question of 'Why?', squared, applied to FILL IN HERE, squared? You might try asking him to rephrase his question, or, perhaps reply with 'Why do you ask?' ('Why' tends more toward theology than hard science) Link to comment Share on other sites More sharing options...
Lars Posted November 4, 2007 Author Share Posted November 4, 2007 Haha, sorry to bring back an old thread, but I posted this last year, I didnt end up getting a clean up detention, but what's funny is I didnt even realise I had this account until I tried to sign up again Link to comment Share on other sites More sharing options...
confused Posted November 4, 2007 Share Posted November 4, 2007 lol should this be in Physics? Link to comment Share on other sites More sharing options...
entwined Posted November 4, 2007 Share Posted November 4, 2007 If gravity is a result of an attraction resulting from mass, then why aren't fat girls more popular than thin girls? Link to comment Share on other sites More sharing options...
Dovada Posted November 6, 2007 Share Posted November 6, 2007 Have a look here http://www.dovada.com/forum/viewtopic.php?t=17 it appears to be electrical in nature. Link to comment Share on other sites More sharing options...
ydoaPs Posted November 6, 2007 Share Posted November 6, 2007 Have a look here http://www.dovada.com/forum/viewtopic.php?t=17 it appears to be electrical in nature. That appears to fly in the face of everything we know about gravity. Care to back it up? Link to comment Share on other sites More sharing options...
Phi for All Posted November 6, 2007 Share Posted November 6, 2007 Have a look here http://www.dovada.com/forum/viewtopic.php?t=17 it appears to be electrical in nature.[/quote']That appears to fly in the face of everything we know about gravity. Care to back it up?I suspect ulterior motive whenever someone joins just to lead us to his own site. Link to comment Share on other sites More sharing options...
swansont Posted November 6, 2007 Share Posted November 6, 2007 I suspect ulterior motive whenever someone joins just to lead us to his own site. Ulterior, electric motives? Link to comment Share on other sites More sharing options...
tvp45 Posted November 6, 2007 Share Posted November 6, 2007 "Why is there gravity?" That's easy. Tell your teacher it's there so water balloons will work. Link to comment Share on other sites More sharing options...
ironizer Posted November 9, 2007 Share Posted November 9, 2007 If gravity is a result of an attraction resulting from mass, then why aren't fat girls more popular than thin girls? Because thin girls make guys more horny (usually). The gravitational force between a guy and a fat chick is greater, but most of us have the ability to escape it. Link to comment Share on other sites More sharing options...
insane_alien Posted November 9, 2007 Share Posted November 9, 2007 Because thin girls make guys more horny (usually). The gravitational force between a guy and a fat chick is greater, but most of us have the ability to escape it. In my experience it is usually a matter of taste than of gravity, or the horniness of the woman. for instance, really skinny is just as disgusting and off putting as really fat. a happy medium is best. Link to comment Share on other sites More sharing options...
swansont Posted November 9, 2007 Share Posted November 9, 2007 Would a content aether be a happy medium? Link to comment Share on other sites More sharing options...
Ashish Posted January 25, 2008 Share Posted January 25, 2008 Anotherother fun questions that a lot of teachers wont the awnsers to is: "If I shake this string then I get a wave of string but, what is light a wave of?", the awnser is that it isn't. Which really amuses me for some reason. really thats the question which has disturbed my mind. And I'm to satisfied with you. And i'm in search of it..................... Link to comment Share on other sites More sharing options...
CaptainPanic Posted January 25, 2008 Share Posted January 25, 2008 Since nobody seems to know what gravity exactly is (has anyone ever measured a "graviton" or something like that?), and why it's there... It might be a safe conclusion to say that gravity is merely a model that seems to fit our observations very well. I cannot think of a reason why there shouldn't be another model, without gravity included, that can describe the reality that we measure and see with our eyes. However, such model has not been developed yet, so we assume gravity to be real. It also feels very real when you go head first to the pavement. There are some people who have interesting arguments that say the gravity model is incomplete (they don't seem to disagree with the concept of gravity). They have grouped themselves in a movement (if you can call it that) called "the electric universe". I have read some electric universe webpages (just google it)... and hardcore models seem hard to find on websites. However, in more conventional websites, I also have never seen a good explanation why Saturn's rings don't condense into some spheres (moons). A ring seems to defy gravity. Electric forces can explain rings quite well, since it includes both attraction and repulsion. Gravity, to my knowledge, only includes attraction. If anyone has a good explanation about Saturn's rings, I'm interested. Disclaimer: I have not studied the subject to a great detail. Before stating things I wrote here as a fact, please study the subject, and doublecheck everything. (Ha, quite proud of myself for adding a disclaimer here ). Link to comment Share on other sites More sharing options...
Klaynos Posted January 25, 2008 Share Posted January 25, 2008 What's not (talking of commonly accepted scientific theories) a model that seems to fit what we've observed so far? Link to comment Share on other sites More sharing options...
Realitycheck Posted January 25, 2008 Share Posted January 25, 2008 I don't see how QM even makes a case. What's the point of devising a particle for anything and everything when GR explains it just fine? Link to comment Share on other sites More sharing options...
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