Velocity and time information for a leftward moving car are shown. t = 4.0s v= 4.0 m/s. t = 0.0 v=20.0 m/s. what is the magnitude and direction of acceleration?

Explanation:

Hello,

Based on the information, one could use the following formula to compute the magnitude of acceleration in this case:

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:

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.