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Q8. A. What is slip? What are the factors on which the torque or an induction motor depends?  B) Calculate the pitch factors Kp for a wiping having 24 stator slots, 4 poles, when the coil span is 1 to 6

Q10. two shunt generators X and Y work in parallel. theri external characteristics may be assumed to be liner over their normal working range. The terminal voltage of X falls from 265V on no load to 230V. When delivering 350A to the bus bars, while the voltage falls from 270V on no load to 240V when delivering 400A to the bus bars, calculate the current which each machine delivers when they share a common load of 500A, what is the bus bar voltage under this condition and power delivered by each machine?

Q10. A ship of length 140m, Breadth of 18.5m, draught of 8.1m and a displacement of 17,025 tonnes in sea water, has a face pitch ratio of 0.673. Diameter of the Propeller is 4.8m. The results of the speed trial show that true slip may be regarded as constant over a range of 9 to 13 knots and is 30%, w = 0.5CB-0.05. If fuel used is 20t/day at 13 knots and fuel consumption/day varies as cube of speed of ship, Determine the fuel consumption, when propeller runs at 110 rpm.

Q8. A ship 100 m long floats at a draught of 6 m and in this condition the immersed cross-sectional areas and water plane areas are as given below. The equivalent base area (Ab) is required because of the fineness of the bottom shell.

.

Calculate EACH of the following:

(a) The equivalent base area value Ab;

(b) The longitudinal position of the center of buoyancy from midships;

(c) The vertical position of the center of buoyancy above the base.

Q1. Vessel has gone through very heavy weather. On arrival at safe anchorage, you are conducting your inspection to determine damages to hull.

A. List the areas you will inspect.      B. List your findings of any significance.

C. Write a report to company suggesting repairs if any.

Q2. The half-ordinates(m) of a waterplane, which are 6m apart, are given by: 11,16,24,84,39,42,47,52,40,23,26,46,13,23.

Calculate and compare the areas of waterplane as given by the 1,4,1 rule, the 1,3,3,1 rule and the trapezoidal rule

Q6. a) Describe how the distribution of mass within the ship affects the rolling period. (6)

b) The righting moments of a ship at angles of heel of 0, 15°, 30°, 45°, and 60° are 0, 1690, 5430, 9360 and 9140 kN-m respectively. Calculate the dynamical stability at 60°. (10)

Q7. A. Explain what is meant by ‘assigned summer free board’. B. A ship 120m long has draughts of 6.6m forward and 6.9 aft. The TPC is 20, MCTI cm 101 tonne m and the centre of flotation 3.5m aft of midships. Calculate the maximum position aft at which 240 tonne may be added so that the after draught does not exceed 7.2m

Q6: A. what is ‘form stability’ & ‘weight stability’. b. A Ship of 5000 tonnes displacement enters a drydock trimmed 0.45m by the stern. KM=7.5m., KG=6.0m. MCTC=120 tonnes-m.  The centre of flotation is 60m. Frome aft. Find the effective metacentric height at the critical instant before the ship takes the blocks overall, assuming that the transverse metacentre rises 0.075m.

Q8. A. Describe how the force on the ship’s bottom and the GM vary when grounding takes place.

B) The ½ ordinates of a water plane at 15m intervals, commencing from aft, are 1, 7, 10.5, 11, 11, 10.5, 8, 4 and 0m. Calculate:

(a). TPC;

(b). Distance of the centre of flotation from midships.

(c). Second moment of area of the water plane about a transverse axis through the centre of flotation.

Q1. A. Explain the purpose of the rudder carrier and pintles.

B. The speed of a ship is increased to 18% above normal for 7.5 hours, and then reduced to 9% below normal for 10 hours. The speed is then reduced for the remainder of the day so that the consumption for the day is the normal amount. Find the percentage difference between the distance travelled in that day and the normal distance travelled per day.

Q8. A. Explain the purpose of non-watertight longitudinal subdivision of tanks.

b) A box -barge 30 m long and 9 m beam floats at a draught of 3 m. The centre of gravity lies on the centreline and KG is 3.50 m. A mass of 10 tonne, which is already on board, is now moved 6m across the ship.

i) Estimate the angle to which the vessel will heel, using the formula

ii) Compare the above result with the angle of heel obtained by the metacentric formula. (10)