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Q8. (a) Explain the term thrust deduction with respect to a ship's propeller.  (3)

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

ship speed = 15.6 knots

delivered power = 2600 kW

effective power = 1750 kW

thrust    = 280 kN

propeller efficiency = 65%

apparent slip = 6%

Calculate EACH of the following:

(i) the thrust deduction fraction; (3)

(ii) the Taylor wake fraction; (5)

(iii) the true slip; (3)

(iv) the hull efficiency.  (2)