Q15 of 107 Page 12

A tower subtends an angle of 30° at a point on the same level as its foot. At a second point h metres above the first, the depression of the foot of the tower is 60°. The height of the tower is


Let the AB be the height be the tower


Let D be the point where the tower subtends angle of 30°


Let C be the point where such that CD = h meters. From C the angle of depression subtended at the foot of the tower is 60°


In Δ CDB


tan 60° =


BD = h cot 60°


BD = …………….1


In Δ ADB


tan 30° = AB/ BD


= AB / BD


AB = ×


AB = m

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