We can determine the final velocity via the following kinematic equation:
[tex]v_{final}^2=v_{initial}^2+2a \Delta x[/tex]
Since the sprinter starts at rest this means the initial velocity is zero, a = 1.5 m/s^2 and the difference of x is 20 meters therefore:
[tex]v_{final}^2=0^2+2(1.5m/s^2)(20)\\\\v_{final}^2=60\\\\v_{final}=\sqrt{60}\\v_{final} \approx 7.75 m/s[/tex]
The final velocity is 7.75 m/s
