Throwing a ball in a moving train

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When a tennis ball is thrown straight up inside a moving train, it falls back to the same spot due to the ball, the train, and the surrounding air moving at the same velocity. This phenomenon occurs because the closed environment of the train minimizes external forces like wind. If the ball is thrown from the roof of the train, it will likely be affected by wind resistance, causing it to drift backward. The ball retains its speed due to its kinetic energy, allowing it to maintain a similar velocity to the train. Thus, the results would be comparable whether inside the train or on its roof, barring wind effects.
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If you throw a tennis ball straight up in a moving train, the ball will drop back down on the same spot so you can catch it
right?
Does this happen because i am in a closed space where the air is still?
What would happen if i went on top of the train (so i guess the roof of the train) and did the same experiment?
will the ball be flown backward because of the wind?
 
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nobelium102 said:
If you throw a tennis ball straight up in a moving train, the ball will drop back down on the same spot so you can catch it
right?
Does this happen because i am in a closed space where the air is still?
Right!
What would happen if i went on top of the train (so i guess the roof of the train) and did the same experiment?
will the ball be flown backward because of the wind?
You need not to risk that much. Just take your tennis ball and go to backyard of your house during stormy wind to see what happens.
 
Remember that it's not just the train traveling at 80mph! You, the ball and the air in the carriage all have the same velocity. The wind outside the train is the same wind resistance that a ball would feel if you fired it from standing to 80mph.
 
wind => external force
 
you don't need a moving train to see if a ball moves with wind!
Actualy the question would be why didn the ball remain in its place in space when you threw it in the air and didn go bakward? in fact, you re stick to the train but it's not? why didn it loose the train speed when not being attached to it? well that's cz it's got some kinetik energie which let it move with nearly same speed! and that's why(ignoring wind) u'll get the same results at the top of the train
 
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