Q8 of 107 Page 12

The angle of elevation of the top of a tower at a point on the ground is 30°. What will be the angle of elevation, if the height of the tower is tripled?


Let h be the height of the tower


∴ tan 30°= h/ AB (tan θ = perpendicular / base)


………..1


When the height is tripled h becomes 3h


tan θ = 3h / AB


tan θ = (from 1)


tan θ =


tan θ = √3 ( by rationalizing the denominator)


θ = 60° (tan 60° = √3)


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