section 3.4
DESCRIPTION
Section 3.4. Arc length & area of a sector. Arc Length. Arc Length. Arc Length. Arc Length. To use this formula, must be in radians. Arc Length. #1: Find the radius of an 15 foot arc of a circle that subtends and angle of 15˚. To use this formula, must be in radians. Arc Length. - PowerPoint PPT PresentationTRANSCRIPT
![Page 1: Section 3.4](https://reader035.vdocument.in/reader035/viewer/2022070421/5681624e550346895dd299c2/html5/thumbnails/1.jpg)
ARC LENGTH &AREA OF A SECTOR
Section 3.4
![Page 2: Section 3.4](https://reader035.vdocument.in/reader035/viewer/2022070421/5681624e550346895dd299c2/html5/thumbnails/2.jpg)
Arc Length
![Page 3: Section 3.4](https://reader035.vdocument.in/reader035/viewer/2022070421/5681624e550346895dd299c2/html5/thumbnails/3.jpg)
Arc Length
![Page 4: Section 3.4](https://reader035.vdocument.in/reader035/viewer/2022070421/5681624e550346895dd299c2/html5/thumbnails/4.jpg)
Arc Length
![Page 5: Section 3.4](https://reader035.vdocument.in/reader035/viewer/2022070421/5681624e550346895dd299c2/html5/thumbnails/5.jpg)
Arc Length
To use this formula,must be in radians
𝑆=𝑟 𝜃
![Page 6: Section 3.4](https://reader035.vdocument.in/reader035/viewer/2022070421/5681624e550346895dd299c2/html5/thumbnails/6.jpg)
Arc Length
To use this formula,must be in radians
#1: Find the radius of an 15 foot arc of a circle that subtends and angle of 15˚
𝑆=𝑟 𝜃
![Page 7: Section 3.4](https://reader035.vdocument.in/reader035/viewer/2022070421/5681624e550346895dd299c2/html5/thumbnails/7.jpg)
Arc Length
#2: The diameter of a Ferris Wheel is 200 ft. and θ is the central angle formed as a rider travels from her initial position of P0 to P1. Find the distance she travels if θ = 30˚.
![Page 8: Section 3.4](https://reader035.vdocument.in/reader035/viewer/2022070421/5681624e550346895dd299c2/html5/thumbnails/8.jpg)
Arc Length
#3: One way to construct a 400 meter race trace is to make each straight-away 100 meters long and the semicircles for the inner track 100 meters each. In a 400 meter race, how much of a “head start” should the runner is the 6th lane get over the runner in the 1st lane.
![Page 9: Section 3.4](https://reader035.vdocument.in/reader035/viewer/2022070421/5681624e550346895dd299c2/html5/thumbnails/9.jpg)
Area of a Sector
Derivation
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Area of a Sector
𝐴=12 𝑟 2𝜃
To use this formula,must be in radians
![Page 11: Section 3.4](https://reader035.vdocument.in/reader035/viewer/2022070421/5681624e550346895dd299c2/html5/thumbnails/11.jpg)
Area of a Sector
#4: A lawn sprinkler shoots out water 20 feet and rotates 135˚. Find the area of lawn that is watered by the sprinkler.
![Page 12: Section 3.4](https://reader035.vdocument.in/reader035/viewer/2022070421/5681624e550346895dd299c2/html5/thumbnails/12.jpg)
Area of a Sector
#5: Find the degree measure of an angle that is subtended by an arc of a sector that has an area of 30 square feet if radius of the arc is 10 feet.
𝐴=12 𝑟 2𝜃
![Page 13: Section 3.4](https://reader035.vdocument.in/reader035/viewer/2022070421/5681624e550346895dd299c2/html5/thumbnails/13.jpg)
Area of a Sector
#6: Find the arc length of a sector of a circle that has a central angle of 20˚ and an area of 450 square meters.