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The circumference of the circle is 160 mm. a) if the length of arc AB when <1= 40.05°b) <1 when are AB = 35.62 mm

User Detect
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1 Answer

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Given an arc with length l of a circle with circumference c such that the arc subtends an angle of


\theta

then we must have that


l=(\theta)/(360^0)* c

In this case,


\begin{gathered} c=160\operatorname{mm}\text{ and} \\ \theta=40.05^0 \end{gathered}

Therefore,


l=(40.05^0)/(360^0)*160=17.8\operatorname{mm}

b)

In this case,


\begin{gathered} l=35.62\operatorname{mm}\text{ and} \\ c=160\operatorname{mm} \end{gathered}
\begin{gathered} 35.62=(\theta)/(360^0)*160 \\ \\ \text{this implies that} \\ (35.62)/(1)=(160\theta)/(360^0) \\ \text{ Cross-multiplying, we have} \\ 160\theta=360^0*35.62 \\ \text{therefore} \\ \theta=(360^0*35.62)/(160)=80.15^0 \end{gathered}

Therefore ,

<1 = 80.15 degrees

User Jakob F
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