When we travel in the bus or train that is running at any
speed, for example, 50 km/hr and throw an object from the train it will go backwards far
behind us?
If we consider a bee flying inside the bus/train why does it remain flying at the
same position rather by going forward or backward?
It is all
to do with air resistance and drag. The air inside the train is moving with the same speed as
the train. The bee flying in the air inside the train is only moving at a small speed relative to
the air in the train. However it is moving at this speed PLUS say 50 km/hr relative to the
ground.
However if we throw an object out of the train things are a bit different. At
the instant we throw it out the object is moving at the same speed as the train, say 50 km/hr.
However the air outside the train is 'still' and so the object is moving forwards through this
still air at 50 km/hr. This means that there will be a large amount of air resistance or drag on
the object.
This drag will start to slow the object down but the train is still moving
forwards at 50 km/hr. To us watching from inside the train it seems as if the object has
moved back far behind us – in fact it is really us that have moved forwards in front of the
object.
If you watch someone throwing an object from a train when you were
standing on the track you would see the object move forwards in the same direction as the
train but slow down due to air resistance. The train would move off ahead of it.