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Question
A circus artist is climbing a 20 m long rope, which is tightly stretched and tied from the top of a vertical pole to the ground. Find the height of the pole, if the angle made by the rope with the ground level is 30°.
Solution
It can be observed from the figure that AB is the pole.
In ΔABC,
`"AB"/"AC"` = sin 30°
`"AB"/(20) =1/2`
AB = `20/2`
= 10
Therefore, the height of the pole is 10 m.
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