posted by jasmin .
If you exert a force of 60 N on a car, it moves at a constant velocity. (i.e there is a frictional force of 60 N) What is its mass when you exert 80 N on it, it accelerates from rest to 2.0 m/s in 100 seconds?
v=at => a =v/t =2/100=0.02 m/s²
m=( F2-F1)/a=(80-60)/0.02=1000 kg