Name: _____________________________________________________________ Date: _________________________ Period: ______ Chapter 8: Intro to Trig Topic 7a: Arc Length FORMULA: = Where: S= r= = How do I know if it’s in radians already? If it’s not, convert: = ⋅ Examples: 180 1. In a circle with a radius of 3 centimeters, what is the length, in centimeters, of an arc intercepted by a central angle of 2 radians?  3  4  6  12 2. Find the exact length of the arc created by the shaded region, from a central angle of 2 3 3. The protractor shown at the right has a radius of 2.5" and the angle AOB is measuring 450. What is the length, x, along the outer edge to the nearest hundredth? 4. In a circle, a central angle of subtends an arc of 3 centimeters. Find the length of the radius of the 3 circle to the nearest tenth. Name: _____________________________________________________________ Date: _________________________ 8-7a Homework: Arc Length All work is to be done in your notebook – not on this sheet Period: ______ Find the exact value of each arc length: (remember… exact means no rounding, so stick with π) 1. 2. Find the length of each arc to the nearest tenth: (use your π key at the very end to turn into a decimal) 3. 4. 5. Find, in centimeters, the length of an arc intercepted by a central angle of 4 radians in a circle with a radius of 3.5 cm. 6. A sector has a radius of 12 cm. and an angle of 65º. To the nearest tenth of a cm., find its arc length. 7. A banner is made in the shape of a sector, shown below. Angle MOP measures 1 radian, and the radius of the sector measures 10 feet. A blue rope piping is placed around the outside edge of this sector banner. How many feet of rope piping is needed to outline the entire sector? 8. A wedge-shaped slice is cut from a circular pizza. The radius of the pizza is 8 inches and the rounded edge of crust of the slice measures 6.4 inches. What is the angle of the pointed end of the pizza slice, in radians to the nearest tenth?