Finding average/final velocity and acceleration.

AI Thread Summary
To find the average velocity, divide the total displacement of 720m by the total time of 45s, resulting in an average velocity of 16.0 m/s. The final velocity can be calculated using the equation Vf = Vi + at, where initial velocity (Vi) is 10.0 m/s. The acceleration can be determined using the formula d = Vit + 1/2at^2, leading to a consistent solution for the problem. Understanding that average velocity is the mean of initial and final velocities simplifies the calculation. The discussion highlights the importance of distinguishing between average and final velocity in kinematic equations.
HelloImAsh
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Homework Statement


An object with an initial velocity of 10.0m/s moves 720m in 45s along a straight line iwht constant acceleration. For the 45s interval, find its average velocity, final velocity and acceleration.

Homework Equations


5 Kinematic equations:
d=1/2(Vf+Vi)t
Vf=Vi+at
d=Vit+1/2at^2
d=Vft-1/2at^2
Vf^2=Vi^2+2ad

I can't seem to distinguish between the final and average velocity. The acceleration part is simple enough. Thanks :)
 
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HelloImAsh said:
I can't seem to distinguish between the final and average velocity. The acceleration part is simple enough. Thanks :)

average velocity = total displacement divided by total time

(which, for constant acceleration, = (vi + vf)/2)
 
Thanks, I got the answer.
 
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