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Homework Help: How much time does the blood take to reach its final velocity?

  1. Sep 30, 2007 #1
    the left ventricle of the heart accleartes blood from rest toi a velocity of +26 cm/s.
    A)if the displacement of the blood during the acceleration is +20 cm, determine its accleatrion in (cm/s)
    b) How much time does the blood take to reach its final velcoity?


    Kindly plz provide steps by steps so i can learn better!!

    Thanks
     
  2. jcsd
  3. Sep 30, 2007 #2
    You are given final and initial velocities and displacement, but not time.

    The equation for accelerated motion when time is unknown is
    A) Vf^2 = Vi^2 + 2*a*s where Vf is final velocity and Vi is initial velocity. Solve for a.

    Now that you know a, use your definition of acceleration:
    B) a = (Vi + Vf) / t solve for t.

    You need to know these formulas! They come up again and again in physics.
     
  4. Sep 30, 2007 #3
    What he said, in laTex:

    [tex] V_{final}^{2} = U_{initial}^{2} + 2as [/tex]

    Where:
    V = Final Velocity
    U = Initial Velocity
    a = Acceleration (in ms if U and V and s are in meters.)
    s = Displacement
     
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