ME 221 Statics

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ME 221 Statics Lecture 15Section 4.3
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Homework 5

• Chapter 3 problems
• 48, 51, 55, 61, 62, 65, 71, 72 75
• May use MathCAD, etc. to solve
• Due today

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Homework 6

• Chapter 4 problems
• 10, 11, 18, 24, 39, 42, 43 47
• Must use integration methods to solve
• Due Monday, October 14

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Quiz 4

• Wednesday, October 9

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Last Lecture

• The concepts of distributed loads, centroids and
  center of gravity were presented.

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Centroid of an Area

• Geometric center of the area

• Average of the first moment over the entire area

• Where

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Centroid of an Area

• Is then defined as an integral over the area.

• Integration of areas may be accomplished by the
  use of either single integrals or double
  integrals.

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Centroid of a Volume

• Geometric center of the volume

• Average of the first moment over entire volume

• In vector notation

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Examples