1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Linear Speed/Rotational Speed

  1. Feb 2, 2004 #1
    I can define both terms Linear Speed, Rotational speed,

    but I need to find the formula difference so I can show how

    rotational speed is changed to linear Speed.

    I can not find the formula for either.
  2. jcsd
  3. Feb 2, 2004 #2

    Doc Al

    User Avatar

    Staff: Mentor

    I assume you are talking about how to find the tangential speed (V) of something that is rotating about a point at some angular speed (ω, measured in radians/sec). The relationship is V=ωr, where r is the distance to the axis of rotation.
  4. Feb 2, 2004 #3


    User Avatar
    Staff Emeritus
    Science Advisor

    If the angular speed is ω, measured in radians per second, that means that in 1 second, the "wheel" will turn through ω radians. On a "wheel" of radius r, one radian angle cuts an arc of length r*1= r on the circumference of the wheel (remember that the full circle is 2π radians and the entire circumference is 2πr).
    That is, in one second there is a revolution of ω radians which carries a point on the circumference a distance rω.
    Angular speed ω corresponds to a linear speed of v= rω, just as Doc Al said.
  5. Feb 3, 2004 #4
    Thanks to all.
    I now understand
    v= linear speed
    w= Rotational Speed
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?