 | William Tolmé Maccall - Electric currents, Alternating - 1923 - 530 pages
...combining these as the formulae show. 9. BMS Values, etc. — The EMS value of a wave with harmonics is the square root of half the sum of the squares of the amplitudes of the separate harmonics. Ie if y = a, sin 6 + a2 sin 30 + a5 sin 50 + etc. + b, cos 0... | |
 | Engineering - 1918 - 2826 pages
...2» : 16 = conjugate diameter. To compute the Circumference of an Ellipse (fig. Hi). Вт— Multiply the square root of half the sum of the squares of the two diameters by 3-1 116. ^/P' +"' x 3-141« = cAratmference. ÏTunu.— The to»ninrer»e and conjugate diameters,... | |
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Multiply the square root of half the sum of the squares of the two axes by *, and the product will be nearly = the circumference. Ex. Taking the same example as before, we hare /24' + IT \/ = — X 3,14159 = 66,6433= the circumference nearly. 
