32.5k views
5 votes
A windshield wiper blade turns through an angle of 135°. The bottom of the blade traces an arc with a 5-inch radius. The top of the blade traces an arc with a 23-inch radius. To the nearest inch, how much longer is the top arc than the bottom arc? Round to the nearest whole number.

User Pcans
by
7.7k points

1 Answer

5 votes

Answer: The length of an arc of a circle is given by the formula:

L = rθ

where L is the length of the arc, r is the radius of the circle, and θ is the central angle in radians.

To find the length of the bottom arc, we have:

L1 = r1θ1

where r1 = 5 inches and θ1 = 135° = (135/180)π radians.

L1 = 5(135/180)π = 16.88 inches (rounded to two decimal places)

To find the length of the top arc, we have:

L2 = r2θ2

where r2 = 23 inches and θ2 = 135° = (135/180)π radians.

L2 = 23(135/180)π = 29.07 inches (rounded to two decimal places)

The difference in length between the top arc and the bottom arc is:

L2 - L1 = 29.07 - 16.88 ≈ 12

Therefore, to the nearest inch, the top arc is 12 inches longer than the bottom arc.

Explanation:

User Colin Coghill
by
8.0k points