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Q4. A ship of length 145 m and breadth 23 m floats at a draught of 10 m in sea water of density 1025 kg/m³ with a block coefficient of 0.72.

A geometrically similar model 5 m in length, when tested at a speed of 1.48 m/s in fresh water of density 1000 kg/m³ gives a total resistance of 29.25 N.

Using the data given below, determine the service delivered power for the ship at the corresponding speed to that of the model.

Allowance for appendages = 5%

Allowance for weather = 16%

Quasi-propulsive coefficient (QPC) = 0.71

The frictional coefficient for the model in fresh water is 1.694

The frictional coefficient for the ship in sea water is 1.414

When speed is in m/s with index (n) = 1.825

Wetted surface area (m²) = 2.57 √(∆ × L)