Answer:
Explanation:
Hello,
Based on the information, one could use the following formula to compute the magnitude of acceleration in this case:
[tex]a=\frac{V_f-V_i}{t}[/tex]
Now, final velocity is after the 4.0 s have passed, it means 4.0 m/s. On the other hand, initial velocity is taken into account at t=0.0s. Thus, the acceleration turns out into:
[tex]a=\frac{4.0m/s-20m/s}{4.0s-0.0s}=-4m/s^2[/tex]
The magnitude of acceleration is then 4m/s^2 and the sign suggests the direction; in such a way, since it has a negative value, it means that the acceleration shifts leftwards, which accounts for a breaking.
Best regards.
