Q28 of 49 Page 1

From a point on the ground, the angles of elevation of the bottom and top of a transmission tower fixed at the top of a 10 m high building are 30o and 60o respectively. Find the height of the tower.


Let the point on the ground be A.


Let BC be the height of the building, BC=10m


And CD be the height of the transmission tower, CD=y m(let)


In ΔABC,




AB=10√3m………………………….(1)


In Δ ABD,



(From eq (1) AB=10√3)


10 + y=10 × 3


10 + y=30


y=20m


∴ The height of tramisiion tower =20m.


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