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

Homework Help: Uniform Circular Motion

  1. Apr 24, 2008 #1
    I had a test today, there was a question about uniform circular motion. Isn't the velocity constant since the speed is constant? I know angular velocity is constant, but the question's answers only state constant speed or velocity.

    Thank you.

  2. jcsd
  3. Apr 24, 2008 #2
    Velocity is a vector. Speed is a scalar (the magnitude of the velocity). If the direction of motion changes, the velocity changes, even if the speed is constant.
  4. Apr 25, 2008 #3
    Yes the velocity is constant since the speed is constant, but only for tangential speed, you are forgetting the centripetal component of circular motion. As phlogistonian stated velocity is a vector i.e... speed and direction, a change in both or either will cause an acceleration.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook