Automatic 45711

What grass area can the automatic sprayer spray if it is set to spray at an angle of 120 ° and the water sprays up to a maximum distance of 5 meters?

Correct answer:

S =  26.2 m²

Step-by-step explanation:

$$\begin{gathered} \alpha =120{}^{\circ } \\ r=5\text{m} \\ {S}_1=\pi \cdot r^2=3.1416\cdot 5^2\doteq 78.5398{\text{m}}^2 \\ S=\frac{\alpha }{360}\cdot S_1=\frac{120}{360}\cdot 78.5398=26.2{\text{m}}^2 \end{gathered}$$

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