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Thread: what are dimensions?

  1. #1 what are dimensions? 
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    i always hv problem understanhog this concept.what are dimensions?why do we need to study it?and what r there x y z planes?why do we need them?


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  3. #2  
    Forum Radioactive Isotope MagiMaster's Avatar
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    Look up the (mathematical) term orthogonal. Start with the definition that a straight line is one dimensional. Any direction orthogonal to the existing dimensions is a new dimension. (This isn't rigourous, but it gives the basic idea.)


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  4. #3  
    Administrator KALSTER's Avatar
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    Dimensions are the available ranges of motion. We experience three spacial dimensions, which means you can define the position of an object with three numbers that indicate the position of that object relative to a reference point. Using these numbers we can accurately and thus usefully describe the relative positions of any combination of points in any number of dimensions through time.
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  5. #4 Re: what are dimensions? 
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    Quote Originally Posted by m.khan
    i always hv problem understanhog this concept.what are dimensions?why do we need to study it?and what r there x y z planes?why do we need them?
    Given your question, you probably do not need them.

    There are good careers available for shepherds.
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  6. #5 thanks guys 
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    thanks guys.spacially dr victor thank u so much.for ur kind of information i wouldn't mind being a shepherd.if u think asking question is bad,what r u doing on this forum?knowledge should bring u humbleness and modesty.u should be willing to benefit others with ur knowledge.i have no reason to get impressed from an arrogant scientist who doesn not know how to use his knowledge to benefit others.isn't a shepherd better.
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  7. #6 Re: thanks guys 
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    Quote Originally Posted by m.khan
    thanks guys.spacially dr victor thank u so much.for ur kind of information i wouldn't mind being a shepherd.if u think asking question is bad,what r u doing on this forum?knowledge should bring u humbleness and modesty.u should be willing to benefit others with ur knowledge.i have no reason to get impressed from an arrogant scientist who doesn not know how to use his knowledge to benefit others.isn't a shepherd better.
    He's probably just annoyed by your inability to use the shift key or to type 'you' with more than one letter. And I agree with him on that part: if you have a question, at least take the effort to type it properly.

    That said: more general, you could consider a dimension to be a "direction" in which something can change e.g. a chess board has 2 spatial dimensions, but you could see the game as 32-dimensional: the number of pieces that can change place (or even 64 dimensional, because they can move in two spatial dimensions). An object moves in 6 dimensions: the normal 3 spatial directions and 3 rotational "dimensions". For mechanical systems, this is also called 'degree of freedom' e.g. a human hand has 26 degrees of freedom, which means that you need 26 dimensions to accurately describe the posture of one hand.

    This probably isn't the most mathematically sound way to describe it, but I hope it is a bit clear.
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    26 dimensions
    Sure, but each one of them described using only three base dimensions.
    Disclaimer: I do not declare myself to be an expert on ANY subject. If I state something as fact that is obviously wrong, please don't hesitate to correct me. I welcome such corrections in an attempt to be as truthful and accurate as possible.

    "Gullibility kills" - Carl Sagan
    "All people know the same truth. Our lives consist of how we chose to distort it." - Harry Block
    "It is the mark of an educated mind to be able to entertain a thought without accepting it." - Aristotle
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  9. #8  
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    Quote Originally Posted by KALSTER
    26 dimensions
    Sure, but each one of them described using only three base dimensions.
    You are missing the point.

    Bender is correct. Each degree of freedom is a dimension. You need 26 parameters to describe the configuration of a hand.

    There is no such thing as a "base dimension".
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  10. #9 Re: what are dimensions? 
    Forum Freshman DrNesbit's Avatar
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    Quote Originally Posted by m.khan
    i always hv problem understanhog this concept.what are dimensions?why do we need to study it?and what r there x y z planes?why do we need them?
    Video game with 1 dimensional movement : http://www.thepcmanwebsite.com/media...pace_invaders/
    Video game with 2 dimensional movement : http://www.pouetpu-games.com/index.p...on=2&game_id=1
    Video game with 3 dimensional movement : Quake, Doom 3, heck, any modern 3D game where you can jump or fly.
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  11. #10 Re: what are dimensions? 
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    Quote Originally Posted by DrNesbit
    Quote Originally Posted by m.khan
    i always hv problem understanhog this concept.what are dimensions?why do we need to study it?and what r there x y z planes?why do we need them?
    Video game with 1 dimensional movement : http://www.thepcmanwebsite.com/media...pace_invaders/
    Video game with 2 dimensional movement : http://www.pouetpu-games.com/index.p...on=2&game_id=1
    Video game with 3 dimensional movement : Quake, Doom 3, heck, any modern 3D game where you can jump or fly.
    If you can also roll, pitch and yaw then you need six degrees of freedom to describe flight.
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  12. #11  
    Administrator KALSTER's Avatar
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    Ok then.
    Disclaimer: I do not declare myself to be an expert on ANY subject. If I state something as fact that is obviously wrong, please don't hesitate to correct me. I welcome such corrections in an attempt to be as truthful and accurate as possible.

    "Gullibility kills" - Carl Sagan
    "All people know the same truth. Our lives consist of how we chose to distort it." - Harry Block
    "It is the mark of an educated mind to be able to entertain a thought without accepting it." - Aristotle
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  13. #12  
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