A 8000 kg engine pulls a train of 6 wagons,each of 2000 kg ,along a horizontal track.If the engine exerts a force of 40000 N and track offers a frictional force of 4000N,then calculate the acceleration of the train.
Answers
Answer:
ANSWER
Given : Mass of engine M=8000 kg
Mass of each wagon m=2000 kg
Frictional force acting in backward direction f=5000 N
(a) : The net force acting on the train F
′
=F−f=40000−5000=35000 N
(b) : Let the acceleration of the train be a
∴ F
′
=(5m+M)a
35000=(5×2000+8000)a ⟹a=1.944 ms
−2
(c) : External force is applied directly to wagon 1 only. The net force on the last four wagons is equal to the force applied by wagon 2 by wagon 1.
Let the acceleration of the wagons be a
′
35000=(5m)a
′
⟹35000=10000×a
′
Acceleration of the wagons a
′
=3.5 ms
−2
Mass of last 4 wagons m
′
=4×2000 kg
∴ Net force on last 4 wagons F
1
=8000×3.5 =28000 N
Thus force on wagon 2 by wagon 1 is 28000 N.
Explanation:
hope it's help
see the attachment to get a pictorial idea of your question.
F= force (40,000N)
f= friction (4000N)
net movement is in direction of force.
force of movement= F-f ==> 36000N.
mass of whole setup is----- mass of engine + wagons ==> 8000+12000= 20000kg.
.
.
.
now, we found both force and mass. ahh, something struck you write? yes, the same old formula:-
F = m x a
36000= 20000a
a= 36000/20000
a= 1.8 m/s^2
ACCELERATION IS 1.8 m/s^2.
