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Brainteasers

Dropping a ball inside a moving train

physicsrelativityinertiaclassic

You stand in the aisle of a train travelling in a straight line at a steady 100 km/h. You hold a ball at shoulder height and let go.

  1. Where does the ball land: at your feet, behind you, or ahead of you?
  2. What changes if the train is braking when you drop it?
  3. Someone standing on the platform watches through the window. What path do they see the ball take?
Show a hint

The ball is moving with the train before you release it. Nothing stops it continuing to do so.

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