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A Vertical Pole is 90m High and the Length of Its Shadow is 90 √ 3 . What is the Angle of Elevation of the Sun ? - Mathematics

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Question

A vertical pole is 90m high and the length of its shadow is `90sqrt(3)`. what is the angle of elevation of the sun  ?

Sum

Solution

Let AB be the pole and BC be its shadow.

In ΔABC,

tanθ = `"AB"/"BC"`

⇒ `tanθ = 90/(90sqrt(3)) = 1/sqrt(3)`

But, `tan30^circ = 1/sqrt(3)`

∴ `θ = 30^circ`

Thus , the angle of elevation is `30^circ`.

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Heights and Distances - Solving 2-D Problems Involving Angles of Elevation and Depression Using Trigonometric Tables
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Chapter 22: Heights and Distances - Exercise

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Frank Mathematics - Part 2 [English] Class 10 ICSE
Chapter 22 Heights and Distances
Exercise | Q 3

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