Question

A force of 45.0 N is applied to J jr. as he stands stationary at the edge of an ice rink. if he has a mass of 75.0 kg,what is his velocity after 4.00s?

Answer 1

\[ F=ma\]
and
\[m=70.0 kg\]
so you can find J Jr's acceleration
\[a=\frac{F}{m}\]

So now you know both the initial velocity (Vi=0) and the time accelerated (t=4s) so you can use a kinematic to find the final velocity given acceleration and time.