Rectangle
- See Article - Geometric Properties of Structural Shapes
| Area of a Rectangle formula | ||
| \( A_{area} \;=\; a \cdot b \) | ||
| Symbol | English | Metric | 
| \( A_{area} \) = area | \( in^2 \) | \( mm^2 \) | 
| \( a, b, c, d \) = edge | \( in \) | \( mm \) | 
 Rectangle (a two-dimensional figure) is a quadrilateral with two pair of parallel edges. Rectangle (a two-dimensional figure) is a quadrilateral with two pair of parallel edges.
- Circumcircle is a circle that passes through all the vertices of a two-dimensional figure.
- Diagonal is a line from one vertices to another that is non adjacent.
| Circumcircle Radius of a Rectangle formulas | ||
| \( R \;=\; \dfrac{ D' }{2 } \) \( R \;=\; \dfrac{\sqrt{ a^2 + b^2 } }{ 2 }\) | ||
| Symbol | English | Metric | 
| \( R \) = outside radius | \( in \) | \( mm \) | 
| \( D' \) = diagonal | \( in \) | \( mm \) | 
| \( a, b, c, d \) = edge | \( in \) | \( mm \) | 
 Polygon (a two-dimensional figure) is a closed plane figure for which all edges are line segments and not necessarly congruent. Polygon (a two-dimensional figure) is a closed plane figure for which all edges are line segments and not necessarly congruent.
- Quadrilateral (a two-dimensional figure) is a polygon with four sides.
- a ∥ c
- b ∥ d
- a = c
- b = d
| Diagonal of a Rectangle formula | ||
| \( D' \;=\; \sqrt {a^2 + b^2 } \) | ||
| Symbol | English | Metric | 
| \( D' \) = diagonal | \( in \) | \( mm \) | 
| \( a, b, c, d \) = edge | \( in \) | \( mm \) | 

| Distance from Centroid of a Rectangle formulas | ||
| \( C_x \;=\; \dfrac{ b }{ 2 } \) \( C_y \;=\; \dfrac{ a }{ 2 } \) | ||
| Symbol | English | Metric | 
| \( C \) = distance from centroid | \( in \) | \( mm \) | 
| \( a, b, c, d \) = edge | \( in \) | \( mm \) | 
| Elastic Section Modulus of a Rectangle formulas | ||
| \( S_x \;=\; \dfrac{ a^2\cdot b }{ 6 }\) \( S_y \;=\; \dfrac{ a \cdot b^2 }{ 6 }\) | ||
| Symbol | English | Metric | 
| \( S \) = elastic section modulus | \( in^3 \) | \( mm^3 \) | 
| \( a, b, c, d \) = edge | \( in \) | \( mm \) | 
| Perimeter of a Rectangle formulas | ||
| \( P \;=\; 2 \cdot a + 2 \cdot b \) \( P \;=\; 2 \cdot ( a + b) \) | ||
| Symbol | English | Metric | 
| \( P \) = perimeter | \( in \) | \( mm \) | 
| \( a, b, c, d \) = edge | \( in \) | \( mm \) | 
| Plastic Section Modulus of a Rectangle formulas | ||
| \( Z_x \;=\; \dfrac{ a^2 \cdot b }{ 4 } \) \( Z_y \;=\; \dfrac{ a \cdot b^2 }{ 4 } \) | ||
| Symbol | English | Metric | 
| \( Z \) = plastic section modulus | \( in^3 \) | \( mm^3 \) | 
| \( a, b, c, d \) = edge | \( in \) | \( mm \) | 
| Polar Moment of Inertia of a Rectangle formulas | ||
| \( J_{z} \;=\; \dfrac{ a \cdot b }{ 12 } \cdot ( a^2 + b^2 ) \) \( J_{z1} \;=\; \dfrac{ a \cdot b }{ 3 } \cdot ( a^2 + b^2 ) \) | ||
| Symbol | English | Metric | 
| \( J \) = torsional constant | \( in^4 \) | \( mm^4 \) | 
| \( a, b, c, d \) = edge | \( in \) | \( mm \) | 
| Second Moment of Area of a Rectangle formulas | ||
| \( I_{x} \;=\; \dfrac{ a^3\cdot b}{12 }\) \( I_{y} \;=\; \dfrac{ a\cdot b^3}{12 }\) \( I_{x1} \;=\; \dfrac{ a^3 \cdot b}{3 }\) \( I_{y1} \;=\; \dfrac{ a\cdot b^3}{3 }\) | ||
| Symbol | English | Metric | 
| \( I \) = moment of inertia | \( in^4 \) | \( mm^4 \) | 
| \( a, b, c, d \) = edge | \( in \) | \( mm \) | 
| Side of a Rectangle formulas | ||
| \( a \;=\; \dfrac{ P}{2 } - b \) \( b \;=\; \dfrac{P}{2} - a \) | ||
| Symbol | English | Metric | 
| \( a, b, c, d \) = edge | \( in \) | \( mm \) | 
| \( P \) = perimeter | \( in \) | \( mm \) | 
| Torsional Constant of a Rectangle formula | ||
| \( J \;=\; a^3 \cdot b \cdot \left( \dfrac{1}{3} - \dfrac{ 0.21 \cdot a }{ b } \cdot \left( 1 - \left( \dfrac{ a^4 }{ 12 \cdot b^4 } \right) \right) \right) \) | ||
| Symbol | English | Metric | 
| \( J \) = torsional constant | \( in^4 \) | \( mm^4 \) | 
| \( a, b, c, d \) = edge | \( in \) | \( mm \) | 
