41.5k views
4 votes
a 15 inch long windshield wiper blade swipes in arc of 120°. How many square inches of a windshield’s surface area does the blade cover in one swipe

User Sasse
by
3.4k points

1 Answer

4 votes

Answer:

The blade covers an area of 235.714 square inches in one swipe

Explanation:

In this question, we are to calculate the area that is covered by blade cover of the windshield wiper blade in 1 swipe.

To calculate this, we shall be using the formula for the area of the sector. The sector in this case subtends an angle of 120 degrees at the centre.

Mathematically, the area covered by the blade in one swipe is

A = θ/360 * pi * r^2

where θ = 120 degrees and r = 15 inch

A = 120/360 * 22/7 * 15^2

= 1/3 * 22/7 * 225 = 22 * 75/7 = 235.714 square inches