Exam Question

(a) List the variables which affect the force on Rudder (6)

(b) A ship of 12000 tonne displacement has a rudder 15m3 in area, whose centre is 5m below the waterline. The metacentric height of the ship is 0.3m and the centre of buoyancy is 3.3m below the waterline. When travelling at 20knots the rudder is turned through 30 degrees. Find the iniital angle of heel if the force Fr perpendicular to the plane of the rudder us given by Fr = 577 A v^2 Sin∝ N. Allow 20% for the race effect (10)