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Question
The string of a kite is 150 m long and it makes an angle of 60° with the horizontal. Find the height of the kite from the ground.
Solution
Let h be the height of the kite.
PB be the length of string such that PB = 150 m.
In right-angled ΔBPA,
sin 60° = `h/150`
⇒ `sqrt3/2 = h/150`
⇒ h = `(150sqrt3)/2`
⇒ h = `75sqrt3`
h = 1.732 x 75
h = 129.9 m
Hence, the height of kite above the ground = 129.9 m.
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