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PROPERTIES OF PLANE FIGURES

AREA
FIGURE CENTROID MOMENTS
OF INERTIA
Arc Segment
r sinD
r r D ----
C

Quarter and Semicircular Arcs
2r
y y ----
C
S

Circular Area
S r 4
I I
x
y
---- 4 4
r
I S 2
z

Semicircular Area S r 4
I I
y
x
8
4r § S 8 ·
4
y y 3S I ¨ © 8 9S ¹ ¸ r
x
C
S r 4
I 4
z
Quarter-Circular Area S r 4
I I
4r x y 16
x x 3S § S 4 ·
C
4r I I ¨ © 16 9S ¹ ¸ r 4
y
x
y y 3S 4
C
I S 8 r
z
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