Results 1 to 5 of 5
Like Tree1Thanks
  • 1 Post By SlipEternal

Math Help - how can a line in space have non zero acceleration?

  1. #1
    Junior Member
    Joined
    Mar 2011
    Posts
    40
    Thanks
    1

    how can a line in space have non zero acceleration?

    [img]http://puu.sh/55VTj.png[/img] (edit: img tags don't work but you can click it)

    okay, so for this question, i figured out that circle/ellipse/hyperbola involves trig functions when you parametrize it in terms of 't' i.e. x=cost y=sint for a circle, so when you differentiate it twice to get the acceleration function it will have a trig function which is non-constant since trig functions oscillate

    okay, and for parabola, i can see that if y=x^2 then x=t and y=t^2 so y will be a constant acceleration when differentiated twice

    but for a straight line i.e. y=x then you have x=t y=t and when you differentiate both 2 times you have a(t)= <0, 0> which is a zero acceleration. how can a straight line have non-constant non-zero acceleration?
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor
    Joined
    Nov 2010
    Posts
    1,937
    Thanks
    785

    Re: how can a line in space have non zero acceleration?

    Suppose x = y = t^2.
    Thanks from iragequit
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Junior Member
    Joined
    Mar 2011
    Posts
    40
    Thanks
    1

    Re: how can a line in space have non zero acceleration?

    Quote Originally Posted by SlipEternal View Post
    Suppose x = y = t^2.
    oh damn thank you!
    Follow Math Help Forum on Facebook and Google+

  4. #4
    Forum Admin topsquark's Avatar
    Joined
    Jan 2006
    From
    Wellsville, NY
    Posts
    10,212
    Thanks
    419
    Awards
    1

    Re: how can a line in space have non zero acceleration?

    Quote Originally Posted by iragequit View Post
    [img]http://puu.sh/55VTj.png[/img] (edit: img tags don't work but you can click it)
    Who wrote that question?? The word "strait" has the definition: "of limited spatial capacity; narrow or cramped." Very different from the word "straight."

    -Dan
    Follow Math Help Forum on Facebook and Google+

  5. #5
    MHF Contributor

    Joined
    Apr 2005
    Posts
    16,454
    Thanks
    1868

    Re: how can a line in space have non zero acceleration?

    Strictly speaking a "line in space" does NOT have "acceleration" at all! A "line in space" is a geometric concept, not physics.

    You can, of course, write parametric equations for a straight line or curve in space, in terms of parameter "t" and then think of "t" as "time" and the line as the path of an object moving. (Personally, I dislike forcing physics terms on mathematics concepts like that.)

    Then we can have "non-zero acceleration" just as a car moving down a straight road can speed up or slow down.
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Equation of a line in 2-space
    Posted in the Pre-Calculus Forum
    Replies: 4
    Last Post: March 29th 2011, 12:50 PM
  2. Equations of a line in three space.
    Posted in the Pre-Calculus Forum
    Replies: 4
    Last Post: March 26th 2011, 06:00 PM
  3. eq. of line in space.
    Posted in the Pre-Calculus Forum
    Replies: 2
    Last Post: December 30th 2008, 03:49 AM
  4. Line between circles in space?
    Posted in the Advanced Math Topics Forum
    Replies: 6
    Last Post: June 11th 2007, 11:49 PM
  5. vector - line in 3 space help!
    Posted in the Pre-Calculus Forum
    Replies: 2
    Last Post: March 22nd 2007, 05:36 PM

Search Tags


/mathhelpforum @mathhelpforum