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प्रश्न
A kite is flying at a height of 45 m above the ground. The string attached to the kite is temporarily tied to a point on the ground. The inclination of the string with the ground is
60°. Find the length of the string assuming that there is no slack in the string.
उत्तर
Let C be the position of kite above the ground such that it subtends an angle of 60° at point A on the ground.
Suppose the length of the string, AC be l m.
Given, BC = 45 m and ∠ BAC = 60°.
In ΔABC:
`sin60^@=(BC)/(AC)`
`therefore sqrt3/2=45/l`
`rArrl=(45xx2)/sqrt3=90/sqrt3=30sqrt3`
Thus, the length of the string is`30sqrt3`.
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