Centroids of Plane Areas
The controid of square, rectangle, circle, semicircle and rightangled triangle.
The centroid of an area is the point where the whole area is considered to be concentrated.
Square
Distance
x = a / 2 (1a)
y = a / 2 (1b)
Area
A = a^{2} (1c)
Rectangle
Distance
x = a / 2 (2a)
y = b / 2 (2b)
Area
A = a b (2c)
Circle
Distance
x = r (3a)
y = r (3b)
Area
A = π r^{2} (3c)
SemiCircle
Distance
x = 4 r / (3 π) (4a)
y = r (4b)
Area
A = π r^{2}/ 2 (4c)
Rightangled Triangle
Distance
x = b / 3 (5a)
y = h / 3 (5b)
Area
A = b h / 2 (5c)
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