Pocketbook of Useful Formulæ and Memoranda
for Civil and Mechanical Engineers

279 OF ENGINEERING FORMULÆ. Velocity of Waves in Feet per Second, when Length DOES NOT EXCEED THE DEPTH OF WaTEE. Length of Wave in feet. Length .. j 2 | 4 j 6 j 8 | 10 20 j 30 40 50 Velocity . |2'57j3-63'4'46 5'14 5‘73 8’13 9’95 i i I _J * 11-50 12-85 Length.. 100 j 200 j 300 500 jl000i200o|300o| 4000 10,000 Velocity. 118’2 25’731’5 40-6|57’3'8V3 99-6 115 182 FORM OF WAVES. When waves are very long compared with their height, their form may be approximately deter- mined by dividing the length of the wave, as measured from crest to crest, into a given number of equal parts and dividing the circumference of a circle (whose diameter = the height of the wave) into the same number of equal parts as shown in the diagram—the outline of the wave passes nearly through the intersection of horizontal and vertical lines projected from such point. The lengths of ordinates are given below for divisions of a wave into 16 and 32 parts.