Answer:
[tex]3.8\text{m}/ \text{s}^2[/tex]
Explanation:
Given: At the starting gun, a runner accelerates at 1.9 m/s2 for 5.2 s. The runner’s acceleration is zero for the rest of the race.
To Find: the speed of the runner at t = 2.0 s.
Solution:
initial speed of runner([tex]\text{u}[/tex]) = [tex]0[/tex] [tex]\text{m}/ \text{s}^2[/tex]
acceleration for first 5.2s of race= [tex]1.9[/tex] [tex]\text{m}/ \text{s}^2[/tex]
to find speed of runner at , [tex]\text{t}=2\text{s}[/tex]
Using first equation of motion,
[tex]\text{v}=\text{u}+\text{at}[/tex]
putting values in the equation
[tex]\text{v}=0+1.9\times2[/tex]
[tex]\text{v}=3.8[/tex] [tex]\text{m}/ \text{s}^2[/tex]
So,
The speed of the runner at [tex]\text{t}=2\text{s}[/tex], is [tex]3.8\text{m}/ \text{s}^2[/tex]
