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?.
(In reply to re: well...
i agree to the ball through the dip having to more average speed...
but it covers more distance also, like
\ / |
\ / |h
distance travelled is sq. root of d^2+(4xh^2)
instead of d in the other case