The angle of elevation of the top of a tower is 30^{0}. If the height of the tower is doubled, then the angle of elevation of its top will also be doubled.

False

Let height of tower is h and BC = x m.

In ∆ABC, tan 30°= AC/BC = h/x

…eq. 1

Now let height be 2h (doubled)

In

⇒ θ = tan^{-1}(1.15) < 60°

(∵ tan^{-1} (1.15) = 49°)

Hence, the angle of elevation is not doubled when height is doubled.

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