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Question
The tops of two poles of height 16 m and 10 m are connected by a wire of length lmetres. If the wire makes an angle of 30° with the horizontal, then l =
Options
26
16
12
10
Solution
Let AB and CD be the poles such that AB = 16 m and CD = 10 m.
The given information can be represented as
Here, AC is the length of wire which is l.
Also, AE = AB − BE = 16 m − 10 m = 6 m
We have to find the length of wire l .
So we use trigonometric ratios.
In triangle ACE,
`sin C= (AE)/(EC)`
`⇒ sin 30°=6/l`
`⇒1/2=6/l`
`⇒ l=12`
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