Page 43 - ebook fluid mechanics_finalize

FLUID MECHANICS

Example 2

2
Calculate the atmospheric pressure in N/m if the level of mercury in a Barometer (Figure
3.9) tube is 760 mm above the level of the mercury in the bowl? Given the specific gravity

3
3
of mercury is 13.6 and specific weight of water is 81.9  10 N / m .

Figure 3.9 : Baromoter

Solution :

p =  m  h
A

Putting h = 760 mm = 0.76 m


While  = S of mercury  of water
m
3
 = 13 6 .  . 9 81 10 N / m 3
m

From p =  m  h
A

3
So p A = 13 6 .  . 9 81 10  . 0 76

= 101 3 . kN / m 2

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