Composite Shapes
For more complex areas, it is often easier to divide the area into a series of "simpler" shapes. The second moment of area for the entire shape is the sum of the second moment of areas of all of its parts about a common axis. This can include shapes that are "missing" (i.e. holes, hollow shapes, etc.), in which case the second moment of area of the "missing" areas are subtracted, rather than added. In other words, the second moment of area of "missing" parts are considered negative for the method of composite shapes.
Read more about this topic: Second Moment Of Area
Famous quotes containing the words composite and/or shapes:
“A positive learning climate in a school for young children is a composite of many things. It is an attitude that respects children. It is a place where children receive guidance and encouragement from the responsible adults around them. It is an environment where children can experiment and try out new ideas without fear of failure. It is an atmosphere that builds children’s self-confidence so they dare to take risks. It is an environment that nurtures a love of learning.”
—Carol B. Hillman (20th century)
“Runs falls rises stumbles on from darkness into darkness
and the darkness thicketed with shapes of terror
and the hunters pursuing and the hounds pursuing
and the night cold and the night long and the river
to cross and the jack-muh-lanterns beckoning beckoning
and blackness ahead”
—Robert Earl Hayden (1913–1980)