Page 66 - ebook fluid mechanics_finalize

FLUID MECHANICS

Exercise 6

1. In a hydraulic jack a force F, is applied to a small piston that lifts the load on the large

piston. If the diameter of the small piston is 15 mm and that of the large piston is 180
mm, calculate the value of F required to lift 1000 kg. Ans. 68.2 N

2. Two cylinders with pistons are connected by a pipe containing water. Their diameters

are 75 mm and 600 mm respectively and the face of the smaller piston is 6 m above

the larger. What force on the smaller piston is required to maintain a load of 3500 kg

on the larger piston? Ans. 276 N

3. A rectangular pontoon 5.4 m wide by 12 m long, has a draught of 1.5 m in fresh water

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(density 1000 kg/m ). Calculate:
i. the mass of the pontoon,

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ii. its draught in the sea water (density 1025 kg/m ). Ans. 97200 kg, 1.47 m

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4. A ship floating in sea water displaces 115 m . Find
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i. the mass of the ship if sea water has a density of 1025 kg/m ,

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ii. the volume of fresh water (density 1000 kg/m ) which the ship would displace.
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Ans. 117875 kg, 118 m

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