Question

a car has two wipers which do not overlap each wiper has blade of length 21 CM sweeping through an angle 120°find the total area cleaned at each sweep of the blades​

Answer 1

area of cleaned by sweeper =2×area of two sectors

2×22/7 × 21 ×21

= 924cmsq

Answer 2

Answer:

Step-by-step explanation:

The area of the sector = Ф/360πr²

Where Ф is the angle subtended at the center of the circle and in this case the angle through which the blade sweeps.

The length of the blade is the radius of the sector.

Given that the blades are equal in length the area swept is equal for the two blades.

Area swept = 120/360 × 21² × 22/7 = 462 cm²

For the two blades we have :

2 × 462 = 924 cm²

The area swept is thus :

924 cm²