Two identical balls roll across the top of a table on parallel paths. One of the balls has to roll down into and up out of a dip in the table. The other ball rolls on the flat all the time. Which ball gets to the far side of the table first, and why?.

Both will reach the far end simultaneously.
(Assuming ideal conditions like no slip while rolling etc etc.)

The ball entering the dip faces same amount of acceleration and deceleration in 1st half and 2nd half of its journey respectively.

Posted by Taggart on 2010-06-27 17:12:25