Question

How much force is needed to put a 3000 kg vehicle to rest if initially moving at 16.67 m/s and if this force is to be applied on the vehicle for 30.0 seconds?

Answer 1

$$F=ma=m\frac{\Delta v}{\Delta t}\\ =\rm 3000\: kg*\frac{16.67\: m/s}{30.0\: s}=1667\:N$$