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प्रश्न
An electric pole is 10 m high. A steel wire tied to the top of the pole is affixed at a point on the ground to keep the pole upright. If the wire makes an angle of 45° with the horizontal through the foot of the pole, find the length of the wire.
उत्तर
Let AC be the wire length, hm and C be the point, makes an angle of 45°
In a triangle, ABC, given that height of the electric pole is BC = 2m and angle C = 45°
Now we have to find the length of wire.
So we use trigonometrically ratios.
In a triangle ABC,
`sin C = "Opposite side"/"Hypotenuse"`
`=> sin 45^@= 10/h`
`=> 1/sqrt2 = 10/h`
`h = 10sqrt2`
Therefore h = 14.1
Hence the length of wire is 14.1 meters
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