The Fox and The Duck
A duck that is being chased by a fox saves itself by sitting at the center of circular pond of radius r. The duck can fly from land but cannot fly from the water. Furthermore, the fox cannot swim. The fox is four times faster than the duck. Assuming that the duck and fox are perfectly smart, is it possible for the duck to ever reach the edge of the pond and fly away to its escape from the ground?
as the speed of dog is 4 times faster than duck...so the duck can actually revolve around the centre faster than dog upto radius r/4... the duck would reach a little less than r/4 first and keep revolving until the dog stands opposite to it...then it has to move a distance of 3r/4 more...so with v speed, it would take her time t1=3r/4v...to catch her dog needs to travel 3.14r distance with 4v speed...so the dog would take 3.14r/4v time.
ReplyDeleteas t2>t1, so the duck would reach first. An intelligent dog would never make a chase.
thnx for really nice explanation....
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