I have the question "A car moves off from rest with an acceleration of $2.22 m/s^2$ over a time of $12.1s$. Calculate the speed it reaches in units of $m/s$. What is this speed in units of $km/h$"
I know that the acceleration $(a)$ is $2.22[m/s^2]$ and the time $(t)$ is $12.1[s]$ and the formula for speed is $V = \large{s \over t}$.
By putting these values in I get $V = \large{2.22[m/s^2] \over 12.1[s]}$, however the answer for this is $0.18[m/s^3]$ and it should have the unit of $[m/s]$. I am not sure which units I need to change.
In the expression $v = s/t$, $s$ is distance, not acceleration (and the formula governs motion at constant velocity, not accelerating motion). The formula that governs acceleration (from rest) is $v = at$. If you multiply rather than divide, you should get the right units.