The theory and practice of modern framed structures : designed for the use of schools, and for engineers in professional practice (1897)
Johnson, J. B. (John Butler), 1850-1902, Bryan, C. W. (Charles Walter), 1863-1927, Turneaure, Frederick Eugene, 1886- · New York : J. Wiley & Sons · leaf 149
c., upon their corre-sponding horizontal lines, thus fixing points c, d, e, etc. Join these also by a smooth curve, and let A^ be that part of the area ofthis new figure above the axis, and A^ thelower portion. Only the upper right-handportion is shown in Fig. 185, but the givenarea may be of any… … =/ bV\dy A J (4) Fig. 185. d = k From (3), b = b^, and considering y negative below the ax\s,J^ d dy = A/ — A,.Substituting in (4), we then haveA/ — A, (5) being the required moment of inertia about a gravity axis, we have = dA(A/ - A, the in which the areas to be measured are. A, the given area,…
