Question

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:
(c) the force of wagon 1 on wagon 2.

Answer 1

Mass of the engine = 8000 kg
Mass of each wagon = 2000 kg,
No.of wagons = 5
mass of total wagon=2000×5
=10000 Kg

Total mass of train = 8000+(2000×5)
= 18000 kg

Force, F = 40000 N
Track resistance , R = 5000 N

Total accelerating force
​​​​​​= F −R
=40000−5000
=35000 N
Let acceleration = y m/s²
Acceleration = Accelerating force / mass
y=35000/18000
= 35/18
=1.94 m/s²

Frictional resistance of 4 wagons = 5000×(2000×4)/18000 =2222 .22 N

Accelerating force on 4 wagons =2000×4÷1.944 =15552 N

Hence total force exertred by wagon on wagon 2,
= Accelerating force +Frictional resistance
=2222 .22+15552
=17774.22 N