A train, and a housefly, are heading directly at each other at a very high speed. The train and the fly then collide. Now obviously, the fly will hit the train, the train will overcome the fly, and the fly will head in the other direction.
Now the laws of physics state for an object to head in one direction, then have a 180 degree change (which the fly undergoes), then there must be an instant where said object experiences no motion. Think of a baseball, the instant the bat hits the ball, it has to stop for a brief second then go the other way.
So the question is: Since this is an elastic collision, and the fly undergoes a 180 degree turn in motion, and since the train is attached to the fly at this instant...
... does the fly, technically, stop the train?
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