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Q7. (a) With respect to a ship’s propeller, explain the term thrust deduction.

(b) The following data were obtained during a ship’s acceptance trials:

Ship speed = 15.4 knots

Delivered power = 2500 kW

Effective power = 1730 kW

Thrust = 274 kN

Propeller efficiency = 64%

Apparent slip = 5%

Calculate EACH of the following:

(i) The thrust deduction fraction;

(ii) The Taylor wake fraction;

(iii) The true slip;

(iv) The hull efficiency.