We are given: Final velocity ([tex]v_f[/tex])=20 m/s .
Time t= 2.51 s and
distance s = 82.9 m.
We know, equation of motion
[tex]v_f = v_i + at.[/tex]
Let us plug values of final velocity, and time in above equation.
[tex]20=v_i+a(2.51)[/tex]
[tex]20=v_i+2.51a[/tex]
Subtracting 2.51a from both sides, we get
[tex]20-2.51a=v_i[/tex] -----------equation(1)
Using another equation of motion
[tex]v_f-v_i=2as[/tex]
Plugging values of vi =20-2.51a, t=2.51 and distnace s=82.9 in this equation.
We get,
[tex]20-(20-2.51a)=2*a(82.90)[/tex]
Now, we need to solve it for a.
20-20+2.51a=165.8a.
-163.29a=0
a=0.
So, the acceleration would be 0 m/s^2.