Question

car initially at rest accelerates at 8 m/s². what is the cars speed after having traveled 40 m

Explanation:

Step1: Identify the kinematic - equation

$v^{2}=u^{2}+2as$

Step2: Substitute values

Given $u = 0$ (starts from rest), $a = 8\ m/s^{2}$, $s=40\ m$. So $v^{2}=0 + 2\times8\times40$.

Step3: Calculate $v$

$v^{2}=640$, then $v=\sqrt{640}\approx 25.3\ m/s$.

Answer:

$25.3\ m/s$