1 knot = 1.689 feet per second
5 knots = 8.44 feet per second
6 knots = 10.13 feet per second
A 30' boat going 6 knots, goes one boat length in about 3 seconds.
At 6 knots a boat will travel 101.3' in ten seconds.
Genoa sheet load = SA X V2 X .00431
SA = sail area in square feet
V = apparent wind velocity in knots