Superman must stop a 120km/h train in 150m to keep it from hitting a stalled car on the tracks.If the train's mass is 3.6x10^5kg,how much force must he exert?Compare to the weight of the train (give as%).How much force does the train exerts on Superman?

Answer 1

vf^2=vi^2+2ad

but a= F/mass

solve for F

Answer 2

be certain to change velocity initial to m/s