Question

Question 7:
A 8000 kg engine pulls a train of 5 wagons, each of 2000 kg, along a horizontal track. If the engine exerts a force of 40000 N and the track offers a friction force of
5000 N, then calculate:
(a) the net accelerating force;
(b) the acceleration of the train; and
(c)the force of wagon 1 on wagon 2

Answer 1

(a) Force by the engine =40000N Friction = 5000an Net accelaterating force = 40000-5000=35000N.  (b)Net acclerating force=35000N Mass of wagons =2000*5=10000kg a=F÷M=35000÷10000=3.5ms^-2  (c) Mass of wagons except 1=4*2000=8000kg.  a =3.5ms^-2  F=ma =8000*3.5=28000N  

Answer 2

Force produced by engine= 40000 N

Frictional force=5000 N

Net Force=40000 N- 5000  N = 35000 N

mass of each wagon=2000 kg

mass of 5 wagons= 5*2000=10000 kg

Force = mass*acceleration

a=F/m

a=35000/10000

a=3.5 m/s2

Net force= 35000 N

Force of each wagon=2000*3.5=7000 N

Therefore Force of wagon 1 on wagon 2= 35000 N - 7000 N = 28000 N

Hope this helps :)