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Homework Help: Circular motion

  1. Oct 10, 2008 #1
    1. The problem statement, all variables and given/known data
    A particle A moves along a circle of radius R= 0.5 m. so that its radius vector [tex]\vec{r}[/tex] relative to point O on th circumference rotates with a constant angular velocity [tex]\omega=0.4 rad/s[/tex]. Find the modulus of velocity and total acceleration.

    3. The attempt at a solution
    The thing which confuses me is that the modulus of radius vector(relative to point on circumference) keeps changing with time. but [tex]\omega=constant[/tex]
    [tex]v=r\omega[/tex]

    This means that v changes with time. Am I right?
     
    Last edited: Oct 10, 2008
  2. jcsd
  3. Oct 10, 2008 #2
    Think about the definition of modulus.
    Does it matter if the direction of the vector is changing?

    Yes, v changes with time, but is the modulus changing?

    HINT:
    modulus can be synonymous with magnitude.
     
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