212.MET December 2022 Q.9(b)

 Three conductors fitted side by side in the stator of a salient-pole alternator. Each generates maximum voltage of 200V (sinusoidal). The angle subtended at the centre of the stator between adjacent conductors is 20 electrical degrees. If the three conductors are connected in series, find(i) the...

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211.MET December 2022 Q.8(b)

 A three phase induction motor is wound for four poles and is supplied from a 50 Hz system. Calculate. i. The synchronous speed; ii. The speed of the rotor when the slip is 4 per cent; iii. The motor frequency when the speed of the rotor is 600 r.p.m          If you are noticing some error in problems kindly comment below.ThanksGiven No of poles P = 4Frequency...

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210.MET December 2022 Q7(b)

  A d.c. motor takes an armature current of 110 A at 480 V. The resistance of the armature circuit is 0.2𝛀. The machine has six poles and the armature is lap-connected with 864 conductors. The flux per pole is 0.05 Wb. Calculate - (i) The speed; (ii) The gross torque developed by the armature. If you are noticing some error in problems kindly comment below.ThanksGivenIa = 110 VV =...

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209.MET December 2022 Q.6(b)

 A diode whose internal resistance is 20 Ω is to supply power to 1000 Ω load from 110 V rms source. Calculate i) peak load current ii) DC load current iii) AC load current IF YOU ARE NOTICING ANY ERROR KINDLY COMMENT BELOWSolutioni) We know that Vmax = Vrms x √2                                 ...

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209.NA November 2022 Q.10(b)

 A watertight bulkhead is 8m high and is supported by vertical stiffeners 700mm apart, connected at the tank top by brackets having 10 rivets 20mm diameter. The bulkhead is flooded to its top edge with sea water. Determine: (a) Shearing force at top of stiffeners, (b) Shear stress in the rivets, (c)...

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208.NA November 2022 Q.9(b)

 A vessel, when floating at a draught of 3.6 m has a displacement of 8172 tonne, KB 1.91 m and LCB 0.15 m aft of midships. From the following information, calculate the displacement, KB and position of the LCB for the vessel when floating at a draught of 1....

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207.NA November 2022 Q.8(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 0 m. Calculate:i. TPCii. Distance of the centre of flotation from midshipsiii. Second moment of area of the water plane about a transverse axis through the centre of flotation. IF YOU ARE NOTICING ANY ERROR KINDLY COMMENT BELOWSolution½ ordinateSMProduct of arealeverProduct...

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206.NA November 2022 Q.7(b)

 A 6m model of a ship has a wetted surface area of 7m2 and when towed in fresh water at 3knots has a total resistance of 35 N. Calculate the effective power of the ship, 120 m long, at its corresponding speed. n=1.825. f from formula SCF=1...

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205.NA November 2022 Q.6(b)

 A ship 150m long and 8.5m draught has a rudder whose area is one sixtieth of the middle-line plane and diameter of stock 320mm. Calculate the maximum speed at which the vessel may travel if the maximum allowable stress is 70 MN/m? the centre of stock 0.9m from the centre of effort and the maximum...

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208.MET November 2022 Q.10(b)

 A diode valve, having the following characteristic is connected in series with a resistor of 10,000 ohm to a 240 V d.c. supply. If a resistor of 40,000 ohms is connected between the anode and cathode, determine the current through the diode.IA (milliamperes) 0  5.5  13  22 ...

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