Question

A legendary Dutch boy saved Holland by plugging a hole in a dike with his finger, which is 1.20 cm in diameter. (a) If the hole was 1.00 m below the surface of the North Sea (density 1030 kg/m3), what was the force on his finger? ON (b) If he pulled his finger out of the hole, how long would it take the released water to fill 1 acre of land to a depth of 1 ft assuming the hole remained constant in size? (A typical U.S. family of four uses 1 acre-foot of water, 1234 m3, in 1 year.) days

Answer 1

Given' 1.20m - dia, Im, 1030 kg/m² ift, = 12 oren (as Force F- Pressure & Area - Pght = pgh. Tio² - 1030x 9.8 X 17.(3.1476)x (0-6XID =(1-1416N (b) = 1834m² From Torricelli principles r-ragh- (2 x 9.8xm = 4.427 m/s Frine equation & Continuity or - F 7 star = 4x(1234) 0² 3.1416x (1.2815) (4427) = 2,464,632.94 8 See = (28.5 days