10.6 Day 2 Circles and Arcs April 21, 2010
10.6 Circles and Arcs
Day 2
Objective:
• Find circumference and arc length.
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10.6 Day 2 Circles and Arcs April 21, 2010
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10.6 Day 2 Circles and Arcs April 21, 2010
Circumference
The circumference of a circle is the distance around the circle.
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10.6 Day 2 Circles and Arcs April 21, 2010
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10.6 Day 2 Circles and Arcs April 21, 2010
Concentric Circles: Circles that lie in the same plane and have the same center.
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10.6 Day 2 Circles and Arcs April 21, 2010
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10.6 Day 2 Circles and Arcs April 21, 2010
Example: The diameter of a bicycle wheel is 22 in. To the nearest whole number, how many revolutions does the wheel make when the bicycle travels 100 ft?
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An arc is measured in ______________.
The arc length is a fraction of a circle's circumference.
Example: An arc of 60o represents 60/360 or 1/6 of the circle. Its arc length is 1/6 the circumference of the circle.
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10.6 Day 2 Circles and Arcs April 21, 2010
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10.6 Day 2 Circles and Arcs April 21, 2010
Example: Find the length of each arc shown in red. Apr 13­8:06 AM
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10.6 Day 2 Circles and Arcs April 21, 2010
Example: Find the length of a semicircle with radius 1.3 m.
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10.6 Day 2 Circles and Arcs April 21, 2010
Question:
Is it possible for two arcs of different circles to have the same measure but different lengths?
Yes
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10.6 Day 2 Circles and Arcs April 21, 2010
Question:
Is it possible for two arcs of different circles to have the same length but different measures?
Yes
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10.6 Day 2 Circles and Arcs April 21, 2010
Congruent Arcs: Arcs that have the same measure and are in the same circle or in congruent circles.
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10.6 Day 2 Circles and Arcs April 21, 2010
Homework: page 570 (27 ­ 39, 42 ­ 47)
*Do not leave your answers in terms of π.
Hey Guys...I bet it took a lot
of math to design this place!!
Gnarly!
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