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प्रश्न
A 10 m high pole is kept vertical by a steel wire. The wire is inclined at an angle of 40° with the horizontal ground. If the wire runs from the top of the pole to the point on the ground where Its other end is fixed, find the lenqth of the wire.
उत्तर
Let AB be the pole and AC be the wire which runs from the top of the pole to the point on the ground where its other end is fixed.
In ΔABC,
sin 40° = `"AB"/"AC"`
⇒ `0.6428 = 10/"AC"`
⇒ `"AC" = 10/0.6428 = 15.6`
Thus , the length of the wire is 15.6 m.
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