154 



H YDR KINETICS. 



2. How much water issues in one hour from the orifice in the 

 bottom of a vessel in which the water always stands 12 feet high, 

 the orifice being T ^ of a square inch ? 



3. How much water per hour will be delivered from an orifice of 

 2 inches area, 25 feet below the surface of a tank kept full, no 

 allowance being made for friction, etc.? 



4. From an orifice, water spouts with a velocity of 96.24 feet. 

 What is the head? Ans. 144ft. 



5. An orifice is 16-08 feet above a horizontal floor. Water spouts 

 to the distance of 80.2 feet. Required the head. 



6. Determine the formula for the velocity of spouting liquids, 

 using meters instead of feet. Ans. v = 4.427 \/h. 



7. A stream of water issues from an orifice under a head of 25 

 meters. Find the velocity of the stream. 



8. How many liters of water will flow through an opening of 10 

 sq. cm. in 20 seconds, the head being kept at 6 m. ? Ans. 531.24 1. 



9. How long will it take for 442,700 cu. cm. of water to escape 

 through a hole 1 centimeter square and 100 meters below the surface 

 of the liquid ? 



10. How long will it take to empty a tank having a base 3 m. by 

 4 m. the water being 25 m. deep, by means of a sq. cm. hole in its 

 bottom ? 



Recapitulation. In this section we have considered 

 the Velocity of spouting liquids; the orifice of Great- 

 est Range ; the method of computing the Volume 

 discharged by an orifice when the Head is con- 

 stant ; the flow of liquids through Pipes and Rivers ; 

 the uses of Water-power ; the five kinds of Water- 

 wheels ; the Lateral Pressure of running water ; 

 the Bursting Pressure when the current is suddenly 

 stopped. 



REVIEW QUESTIONS AND EXERCISES. 



1. (a.) Define Physics. (&.) Define and illustrate four universal 

 properties of matter. 



2. (a.) What is the difference between momentum and energy ? 

 (6.) Find the momentum and (c.) kinetic energy of a 15 Ib. ball 

 moving fifty feet per second. 



