The passenger is 2.3 m away from the door after 3 seconds
Since both train and passenger is moving with a constant acceleration so we can use the second equation of motion to calculate the distance cover by train and the passenger,
Distance cover by the train in 3 seconds
S=ut-0.5at^2
S=0*3-0.5*0.6*3^2=2.7 m
Distance cover by passenger in 3 seconds
S=0*3-0.5*1.2*3^2=5.4 m
Now distance of passenger from the train
s=5+2.7-5.4=2.3 m
Therefore after 3 seconds passenger is 2.3 m away from the door.
Not sure what this has anything to do with physics but in my opinion most do it to teach them a lesson not to do something again others take there anger on their kids e.g if they are drunk and some take pleasure in hitting their kids for no apparent reason.
Answer:
W = 14523.6 J
Explanation:
Given,
Mass = 3.9 Kg
Vertical height , h = 380 m
Work done against gravitational force
W = m g h
g is acceleration due to gravity
W = 3.9 x 9.8 x 380
W = 14523.6 J
Hence, the work done by the gravitational force is equal to W = 14523.6 J