78NA-2 Sr. No. 4

Sr. No. 4
(Time allowed - 3 hours)
N.B. -
Total Marks 100
Afternoon Paper
(1) Attempt SIX questions only with minimum of ONE question from each part.
(2) All questions carry equal marks.
(3) Neatness in handwriting and clarity in expression carries weightage
Section A
1. A box-shaped pontoon is 15 m long, 6 m wide and 3 m deep. It displaces 45 tonnes when floating in
water having a density of 1016 kg/m3. Calculate the load on the end, and side plating when a load of
150 tonnes is placed on the pontoon.
2. The wetted surface of a vessel is 0.4 times that of another of similar form and the displacement of the
latter is 4750 tonnes greater than that of the former. Estimate the displacement of the smaller vessel in
3. A ship 110 m long and 15m beam is floating at an even keel draught of 6m, and the areas of
equidistant transverse sections commencing from aft are 0, 34.4, 74.4, 90.0, 82.6, 52.0 and 0 m'
respectively. Calculate the displacement in tonnes, and also the values of the block and prismatic
coefficients. The density of the water is 1018 kg/m3.
4. A vessel is in the form of a triangular prism 32m. long, 8m. wide at the top, and 5m deep. KG = 3.7m.
Find the initial metacentric height when floating on even keel at 4m. draft Forward and Aft.
5. A ship of 6,000 tonnes displacement has KG = 6m, and KM = 7.3m. The following cargo is loaded:
1000 tonnes, KG 2.5m; 500 tonnes, KG 3.5m; 750 tonnes, KG 9.0m
The following is then discharged:
450 tonnes of cargo KG 0.6m and 800 tonnes of cargo KG 3.0m
Find the final GM.
6. A ship, 120 meter long at the water line has equidistantly spaced semi-ordinates commencing from
forward as 0, 3.7, 7.6, 7.5, 4.6, 0.1 meters respectively. Find the area of the water-plane and the TPC
at this draft.
Section B
7. With the aid of suitable sketches, show the effect of slack tank on a ship’s stability.
8. A ship leaves port upright with a full cargo of timber, and with timber on deck. During the voyage,
bunkers, stores and fresh water are consumed evenly from each side. If the ship arrives at her
destination with a list, explain the probable cause of the list and how this should be remedied.
9. A ship loaded with steel bars in the holds and with steel rolls on deck, berths with an angle of loll
away from the quay. From which side should the steel rolls on deck be discharged first and why?