# How much time does the blood take to reach its final velocity?

1. Sep 30, 2007

### veena

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. Sep 30, 2007

### johnsonandrew

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.

3. Sep 30, 2007

### AbedeuS

What he said, in laTex:

$$V_{final}^{2} = U_{initial}^{2} + 2as$$

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