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Homework Help: Velocity formula

  1. Oct 17, 2004 #1
    velocity formula....

    could anyone tell me the formula for velocity?
    and acceleration?

    thanks,
    Katie
     
  2. jcsd
  3. Oct 17, 2004 #2

    arildno

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    What do you mean??
    If x(t) is a particle's position at time "t", then the velocity of the particle, v(t), is given by:
    [tex]v(t)=\frac{dx}{dt}[/tex]
    That is, the velocity of the object is the rate of change of the position.

    Similarly, acceleration, a(t) is the rate of change of velocity, that is:
    [tex]a(t)=\frac{dv}{dt}=\frac{d^{2}x}{dt^{2}}[/tex]
    Was this what you were after?
     
  4. Oct 17, 2004 #3
    Acceleration = (Initial Velocity x Final Velocity) divided by time, or
    a = (vf-vi) divided by t

    Velocity = d/t or distance divided time.

    However since velocity is a vector quantity (meaning it has magnitude(size), and direction) the d/t doesn't provide you with direction. Depending on the level of physics your doing, you might not be required to have a direction with velocity.
     
  5. Oct 17, 2004 #4
    Velocity is equal to displacement (a vector, as opposed to distance, a scalar) over time. Speed is equal to distance over time.
     
  6. Oct 17, 2004 #5
    [tex] \Delta=[/tex]change in

    Formula for Average Velocity and Acceleration

    <Velocity> = [tex] \frac{\Delta distance}{\Delta time} [/tex]

    <Acceleration> = [tex] {\frac {\Delta Velocity}{\Delta time}} [/tex]
     
    Last edited: Oct 17, 2004
  7. Oct 17, 2004 #6

    robphy

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    Change "velocity" to "average-velocity". :wink:
    Change "acceleration" to "average-acceleration". :wink: :wink:
     
  8. Oct 17, 2004 #7
    true

    I was assuming you weren't talking about instanious velocity or acceleration
     
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