Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Degrees of freedom

  1. Feb 8, 2013 #1
    What are the number of degrees of freedom of
    1)a square sheet moving in XY plane
    2)a triangular lamina moving freely in XY plane
     
  2. jcsd
  3. Feb 8, 2013 #2

    mfb

    User Avatar
    Insights Author
    2015 Award

    Staff: Mentor

    This looks like homework: What did you find out so far?
     
  4. Feb 10, 2013 #3
    A square is composed of many particles with the constraint that distance between every particle is the fixed.so such a square is moving in XY plane.

    if i consider two particles they have 4-1 =3degree of freedom(one is subtracted due to constraint that distance between particles are fixed).if i consider third particle it is defined by two co-ordinates and two constraints and therefore no degree of freedom.....the same for fourth fifth and so on.....

    so my answer is three

    and i dont find any difference in this respect with a triangular lamina......



    I do not know the answer to the question.......please comment on this and say if you have any other opinion.
     
  5. Feb 10, 2013 #4

    mfb

    User Avatar
    Insights Author
    2015 Award

    Staff: Mentor

    Those 3 degrees of freedom just fix the current position of the square. What about its movement?
     
  6. Feb 10, 2013 #5
    if i get generalized co-ordinates i can calculate co-ordinate velocities from it
     
  7. Feb 10, 2013 #6

    mfb

    User Avatar
    Insights Author
    2015 Award

    Staff: Mentor

    Is that related to the original question?
    What do you mean with "get"?
     
  8. Feb 10, 2013 #7
    The question does not ask that .But i told a general principle.For example a simple pendulum which is oscillating in a plane.since its moving along the arc of a circle(distance from orgin is fixed) it has only one degree of freedom....theta.....which is the angle dat the string makes with vertical.......so if i know theta as a function of time.....i can differentiate "theta" to find generalised co-ordinate velocity
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: Degrees of freedom
  1. Degree of Freedom (Replies: 10)

  2. Degrees of freedom (Replies: 4)

  3. Degrees of freedom (Replies: 2)

  4. Degrees Of Freedom (Replies: 6)

Loading...