\fdO'^ - Old Forge Coal Mines

188 HYDROMECHANICS.
(457) (a) Area of piston = Q\ X .7854 = .6013 sq. in.
Pressure per square inch exerted by piston = .6013
83.15 1b.
A column of water 1 foot high and of 1 sq. in. cross-
section weighs .434 pound, and therefore exerts a pressure of
.434 lb. per sq. in. The height of a column of water to exert
a pressure of 83.15 lb. per sq. in.
83 15
must be
^ = 191.6 ft.
the water will rise 191.6 ft. Ans.
Consequently,
The diameter of the hole in the squirt gun has nothing to
do with the height of the water, since the pressure per
square inch will remain the same, no matter what the
diameter may be.
{d) Using formula 34, range = ^4: Ay, we have
/Tky = 4/4 X 10 X 191.6 = 87. 54 ft. Ans.
(458)
(d)
Use formulas 44 and 43.
Q^= All;i/2i[i/ T' - /!;] =
.4lx|x/^^r3^[|/^-/(4y]^
62.21 cu. ft. per sec. Ans.
(a) Area of weir = dd= 2.5 X 2 = 5 sq. ft.
Using formula 43,
v^ = yj = —^ — = 10.44 ft. per sec. Ans.
[c) To obtain the discharge in gallons per hour (d) multi-
ply by 60 X 60 (seconds in an hour) and by 7.48 (gallons in
a cu.
ft.). Thus 52.21 X 60 X 60 X 7.48 = 1,405,910.9 gal.
hour. Ans.
per
(459) First find the coefficient of friction by using
formula 46, and the table of coefficients of friction.
.„ = a.3U->/^ = 2.315l/IJ|J|I = 3.191 ft. per sec.
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