The particle reaches its minimum velocity at t = 0 s or t = 16/15 s
<h3>Further explanation</h3>
Acceleration is rate of change of velocity.
![\large {\boxed {a = \frac{v - u}{t} } }](https://tex.z-dn.net/?f=%5Clarge%20%7B%5Cboxed%20%7Ba%20%3D%20%5Cfrac%7Bv%20-%20u%7D%7Bt%7D%20%7D%20%7D)
![\large {\boxed {d = \frac{v + u}{2}~t } }](https://tex.z-dn.net/?f=%5Clarge%20%7B%5Cboxed%20%7Bd%20%3D%20%5Cfrac%7Bv%20%2B%20u%7D%7B2%7D~t%20%7D%20%7D)
<em>a = acceleration ( m/s² )</em>
<em>v = final velocity ( m/s )</em>
<em>u = initial velocity ( m/s )</em>
<em>t = time taken ( s )</em>
<em>d = distance ( m )</em>
Let us now tackle the problem!
<u>Given:</u>
![x = ( 5t^3 - 8t^2 + 12) ~ m](https://tex.z-dn.net/?f=x%20%3D%20%28%205t%5E3%20-%208t%5E2%20%2B%2012%29%20~%20m)
To find the velocity function, we will derive the position function above.
![v = \frac{dx}{dt}](https://tex.z-dn.net/?f=v%20%3D%20%5Cfrac%7Bdx%7D%7Bdt%7D)
![v = 5(3)t^{3-1} - 8(2)t^{2-1}](https://tex.z-dn.net/?f=v%20%3D%205%283%29t%5E%7B3-1%7D%20-%208%282%29t%5E%7B2-1%7D)
![v = ( 15t^2 - 16t ) ~ m/s](https://tex.z-dn.net/?f=v%20%3D%20%28%2015t%5E2%20-%2016t%20%29%20~%20m%2Fs)
Next to calculate the time to reach its minimum speed, then v = 0 m/s
![0 = ( 15t^2 - 16t )](https://tex.z-dn.net/?f=0%20%3D%20%28%2015t%5E2%20-%2016t%20%29)
![0 = t( 15t - 16)](https://tex.z-dn.net/?f=0%20%3D%20t%28%2015t%20-%2016%29)
![\large {\boxed {t = 0 ~s ~ or ~ t = 16/15 ~ s} }](https://tex.z-dn.net/?f=%5Clarge%20%7B%5Cboxed%20%7Bt%20%3D%200%20~s%20~%20or%20~%20t%20%3D%2016%2F15%20~%20s%7D%20%7D)
<h3>Learn more</h3>
<h3>Answer details</h3>
Grade: High School
Subject: Physics
Chapter: Kinematics
Keywords: Velocity , Driver , Car , Deceleration , Acceleration , Obstacle