. A treatise on architecture & building construction volume VII: tables and formulas . Let nIhdA Then, THE POEYGOX. number of sides of regular polygon;length of one side ; perpendicular distance from the center to a side;number of degrees in each interior angle;area of polygon. A 180(« - 2) n I h Art. 35, § 4. Art. 99, § 4. Rule.— To find the area of an irregular polygon, or anyfigure bounded by straight lines, divide the figure into tri-angles, parallelograms, and trapezoids, and find the area ofeach. The sum of these partial areas will be the area of thefigure. Art. 100, § 4. THE CIRC EE. Re
. A treatise on architecture & building construction volume VII: tables and formulas . Let nIhdA Then, THE POEYGOX. number of sides of regular polygon;length of one side ; perpendicular distance from the center to a side;number of degrees in each interior angle;area of polygon. A 180(« - 2) n I h Art. 35, § 4. Art. 99, § 4. Rule.— To find the area of an irregular polygon, or anyfigure bounded by straight lines, divide the figure into tri-angles, parallelograms, and trapezoids, and find the area ofeach. The sum of these partial areas will be the area of thefigure. Art. 100, § 4. THE CIRC EE. Relation Between Circumference, Diameter, andRadius.— Denoting the circumference by c, the diameter by d, andthe radius by r, 66 TABLES AND FORMULAS. 4 c = * d = 2 ?r r; j = c-, r = —. Art. 103, § 4. 2 7C and Relation Between Arc, Chord, andSegment.— Let / = length of arc of circle; n == number of degrees in arc; r — radius of arc; c — length of chord; h — height of segment. Height of „ Then, r n Art. 105, § 44V? + 4 h1 - c _ Art. 100, § 106, § Then, (a) r = -—^ If ^ is less than , leth r == radius CM of the arc (see Fig. 1);C = chord y4 Z? of the arc;e — chord A C oi half the arc;7/ = height CD of the segment;A = height of segment includedbetween chord A C and arc A C. C* + 4:H\ (b) c (c) A = rr-\Vl%r*-C*-±H\ Art 107, 55 4. Area of Circle.—Let d — diameter of circle;r = radius of circle;A = area of , A ^\*d* = .7854 rf! ,4 = -r2 = r2; Art. 108, § 109, § 4. 4 TABLES AND FORMULAS. 67 Flat Circular Ring.— Rule.— To find the area of a flat circular ring, subtractthe area of the smaller circle from that of the d = the longer diameter;dl — the shorter diameter;A = area of , A = .7854 d2-. 7854 d;2 = .7854 (^-<9)- Art. 110, § 4. Area of a Hector.— Let n — number of degrees in arc;A = area of circle;r = radius of circle;/ = length of arc;a = area of sector. Then, a = ~ == .008
Size: 1449px × 1725px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1890, booksubje, booksubjectdivision26
