A kite is flying at a height of 30 m from the ground. The length of string from the kite to the ground is 60 m. Assuming that there is no slack in the string, the angle of elevation of the kite at the ground is

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Let the kite be at point A. Draw a line perpendicular to the ground at say point B. Since we are assuming no slack in the string, we can assume AC to be the string as in the figure. Join B and C to get a right-angled triangle ABC. Given that the kite is flying 30 m above the ground. So AC = 60 m. So, AB = 30 m. Also the length of the string is 60 m. We are to find the angle made by the string AC with the ground that is, ACB.


In ∆ABC,



Since sin30° =1/2


ACB = 30°.


So, the correct option is (B).

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