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1.1 Arc Length. s = r . r. C = 2 r. What does r stand for?. What does 2 stand for?. This information can help us develop a new formula…. This is called the Arc Length Formula. What does r stand for?. s. r. . What does stand for?. s = r . What does s stand for?.
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1.1 Arc Length s = r
r C = 2r What does r stand for? What does 2 stand for? This information can help us develop a new formula…
This is called the Arc Length Formula. What does r stand for? s r What does stand for? s = r What does s stand for? Units of measure must match. Must be measured in radians.
How to use the Arc Length Formula. Example #1: Given:r = 32 cm and = 3 radians. Find:s (the arc intercepted by a 32 cm radius rotated through 3 radians). s = r Units must match. s = 32 (3) s = 96 cm
How to use the Arc Length Formula. Example #2: Given:r = 6 in. and = 30 Find:s (the arc intercepted by a 6 in. radius rotated through 30). Can’t use…must be a radian. s = r s = 6 (30) s = 6 (/6) Units must match. s = in.
How to use the Arc Length Formula. Example #3: Given:r = 15 in. and s = 35 in. Find: (the angle through which a radius of 15 in. was rotated to intercept an arc that measures 35 in.). s = r The angles are measured in radians. 35 = 15 () = 35/15 = 7/3 radians
How to use the Arc Length Formula. Example #4: Given:r = 6 in. and s = 2 ft. Find: (the angle through which a radius of 6 in. was rotated to intercept an arc that measures 2 ft). The units of measure must match. s = r The angles are measured in radians. 2 = 6() 24= 6() = 4 radians
How to use the Arc Length Formula. Example #5: Given:s = 20 mi. and = /2 Find:r (the radius that was rotated /2 radians and intercept an arc that measured 20 mi.). The units of measure must match. s = r 20 = r(/2) 40/ = r r = 40/miles
How to use the Arc Length Formula. Example #6: Given:s = 36 yd. and = 60 Find:r (the radius that was rotated 60 and intercept an arc that measured 36 yd.). Can’t use…must be a radian. The units of measure must match. s = r 36 = r(60) 36 = r(/3) 108/ = r r = 108/yd
More Arc Length Formula Applications: • Draw Pictures • Apply s = r for every pie shaped figure in the picture. Let’s try…