Question

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

Answer 1

Friction force for engine = $5000N$

a) Net accelerating force,$f_{net}=40000-5000=35000N$

b) acceleration of train, $a=\frac{35000}{10000}=3.5m/s^2$

c) frictional force offer by each wagon is;

$f=\frac{5000}{5}=1000N$

frictional force due to 2nd, 3rd, 4th and 5th wagon is;

$4f=4000N$

$F-4000=4\times 2000\times 3.5=28000$

$F=32000N$