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 and
(b) the acceleration of the train.
​

Answer 1

Answer:

• Net accelerating force = 35000 N
• Acceleration of train = 1.945 m/s²

Explanation:

Given,

• Mass of engine = 8000 kg
• number of wagons in the train = 5
• Mass of each wagon = 2000 kg
• Force exerted by engine = 40000 N
• Friction force offered by track = 5000 N

To find,

• Net accelerating force
• Acceleration of train

Solution,

→ Net accelerating force = (Force exerted by engine) - (Friction force offered by track)

→ Net accelerating force = 40000 - 5000

→ Net accelerating force = 35000 N

Now,

→ Total mass of wagons with engine = (mass of engine) + (mo. of wagons) ( mass of each wagon)

→ Total mass of wagons with engine = 8000 + 5 ( 2000 )

→ Total mass of wagons with engine = 18000 kg

So,

Using formula

→ Force = mass × acceleration

→ Acceleration = Force / mass

→ Acceleration of train = Resultant force / Mass of train

→ Acceleration = 35000 / 18000

→ Acceleration of train = 1.945 m/s²

Therefore,

• Net accelerating force = 35000 N
• Acceleration of train = 1.945 m/s².