Question
a windshield wiper on a a plymouth acclaim is 20 in. long and has a blade of 16in long. if the wiper sweeps through an angle of 110 degree, how large an area does the wiper blade clean?
Answers
Steve
a sector of angle θ in a circle of radius r is 1/2 r^2 θ
110° = 110/180 pi = 1.92
20 * 1.92^2 = 38.4
(20-16)* 1.92^2 = 7.7
38.4-7.7 = 30.7 in^2
110° = 110/180 pi = 1.92
20 * 1.92^2 = 38.4
(20-16)* 1.92^2 = 7.7
38.4-7.7 = 30.7 in^2