Page 30 - ebook fluid mechanics_finalize

FLUID MECHANICS

Example 6 :

Calculate the density, specific weight and weight of one litre of petrol which specific

gravity = 0.7.

Solution :

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Given : Volume, V = 1 liter = 1 x 1000 cm =1000/10 m = 0.001 m3,
Specific gravity, S = 0.7

(i) Density (ρ) = S x 1000 kg/m = 0.7 x 1000 = 700 kg/m .
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(ii) Specific weight () = ρ x g = 700 x 9.81 N/m = 6867 N/m .
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(iii) Weight (W), We know that specific weight () = weight, W ,
volume, V

W W
 = or 6867 = so W = 6867 x 0.001 = 6.867 N.
0 . 001 0 . 001

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