Question

An aeroplane is to go along straight line from A to B, and back again. The relative speed with respect to wind is 5km. The wind blows perpendicular to line AB with speed 5km. The distance between A and B is 1cm. The total time for the round trip is:_________

Answer 1

Answer:

2e/

$\sqrt{v { }^{2} - v {?}^{2} }$