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# A car’s rear windshield wiper rotates 125^(circ) The total length of the wiper mechanism is 25 inches and wipes the windshield over a distance of 14 inches. Find the area covered by the wiper.

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asked 2021-02-18
A car’s rear windshield wiper rotates $$125^(circ)$$ The total length of the wiper mechanism is 25 inches and wipes the windshield over a distance of 14 inches. Find the area covered by the wiper.

## Answers (1)

2021-02-19
Given:
$$theta=125^(circ)$$
$$r_1=25$$ inches
$$r_2=14$$ inches
$$r=r_1-r_2=25-14=11$$ inches
$$theta=125^(circ)*(pi)/180^(circ) approx 2.1817$$ radians
$$1/2 r^2theta=1/2*11^2*2.1817=131.993$$
$$1/2 r^(2/1theta)=1/2*25^2*2.1817=681.781$$
681.781-131.993=549.788

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