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Q4. (a) List the components of residuary resistance. (b) A ship model 6m long has a total resistance of 40N when towed at 3.6 knots in fresh water. the ship itself is 180m long and displaces 20400 tonne. the wetted surface area may be calculated from the formula S= 2.57, Calculate ePn for the ship at its corresponding speed in sea water. f (model)fw =0.492; f (ship)sw =0.421; n=1.825.

Q6. (a) Describe the movement of a ship with negative metacentric height. (b) A ship of 8000 tonne displacement has its centre of gravity 4.5m above the keel and transverse metacenter 5m above the keel when a rectangular tank 7.5m long and 15m wide contains seawater. A mass of 10 tonne is moved 12m across the deck. Calculate the angle of heel:(10) (i) If there is no free surface of water. (ii) if the water does not completely fill the tank.

Q9. A. Describe briefly the inclining experiment and explain how the results are used. B. A ship of 8500 tonne displacement has a double bottom tank 11m wide extending for the full breadth of the ship, having a free surface of seawater. If the apparent loss in metacentric height due to slack water is 14cm, find the length of the tank.

Q6. a) Derive the expression for current and voltage relations between line and phase values in the star and delta cases. Draw vector diagram.

b) Three impedances Z=5+j4 are connected in the form of a delta to the three loads of a balanced 3-phase circuit. The line voltage is 120 Volts.

Find (a) The phase current, (b) Power factor, (c) The volt-ampere in the circuit.

10.A box-shaped barge of uniform construction is 80 m long, 12 m beam and has a light displacement of 888 tonne. The barge is loaded to a draught of 7 m in sea water of density 1025 kg/ m? with cargo evenly distributed. over two end compartment of equal length. The empty midship compartment extending to the full width and depth of the barge is bilged and the draught increases to 10m.

Determine:

(a) the length of the midship compartment.

(b) the longitudinal still water bending moment at midships:

(i) in the loaded intact condition

(ii) in the new bilged condition

Q10. A. Describe the relationship between frictional resistance and: (i)Ship speed; (ii) the wetted area; (iii) surface roughness; (iv) The length of the vessel.  B.A ship travels at 15 knots and has a QPC of 0.865 with a delivered power of 2600 KW. The apparent slip is 5% and the real ship is 28%Calculate the total resistance and the wake friction.

Q6.a) Explain the applications of PN junction diode. (6)

b) A full-wave, 1 -phase rectifier employs a double diode valve, the internal resistance of each element of which may be assumed constant at 500 W. The transformer r.m.s. secondary voltage from the centre-tap to each anode is 300 V and the load has a resistance of 2000 W.  Evaluate:-   (10)

(i) mean load current.

(ii) r.m.s. value of load current

(iii) the d.c. output power

(iv) the input power to the anode circuit

(v) the rectification efficiency

Q10. (A) Compare the effectiveness of a current limiting circuit breaker with that of a HRC fuse. (6)

(B) Evaluate for a frequency of 15 kHz, the amplification and the phase difference between input and output signals of a voltage amplifier using a triode having an amplification factor of 48 and a mutual conductance of 1.2 mA/V with an anode-load resistant of 160 k𝛀. The output p.d. is fed by a coupling capacitor of negligible reactance to a subsequent circuit of resistance 480 k𝛀 and the total shunt capacitance is 90 µF. (10)

Q8. a) What is Prismatic Co-efficient (CP). Derive the formula CP =

, where

= Co-efficient of fineness and

= midship section area co-efficient. (6)
b) A watertight door is 1.2m high and 0.75m wide, with a 0.6m sill. The bulkhead is flooded with seawater to a depth of 3m on one side and 1.5m on the other side. Draw the load diagram and from it determine the resultant load and position of the centre of pressure on the door. (10)

Q6. (a) What is the purpose of conducting an inclining experiment on a new vessel? (6)

(b) When a mass of 6t is moved transversely through a certain distance on a ship of 4300t displacement, the deflection of an 11m pendulum is found to be 120 mm. The transverse meta-centre is 7.25 m above the keel and KG 5.46 m. Find the distance through which 6t was moved. (10)

Q6. The ratios of length, breadth and draught of a vessel are 18.5: 2.5: 1. The water plane area coefficient is 0.73 and the TPC is 0.77 more in sea water than in fresh water. Calculate the beam of the ship and TPC in fresh water. (16)

Q6. a) Explain, with reference to moments about the Centerline, how the list may be removed. (6)

b) A ship of 12,250 tonnes displacement, has KM=8 metres, KB=3.8 metres, KG=8 metres and is floating upright. Find the list if a weight of 2 tonnes, already on board, is shifted transversely through a horizontal distance of 12 metres assuming that the ship is wall-sided (10)