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Question
Find the angle of elevation of the sum (sun's altitude) when the length of the shadow of a vertical pole is equal to its height.
Solution
Let θ be the angle of elevation of the sun. Let AB be the vertical pole of height h and BC be the shadow of equal length h.
Here we have to find the angle of elevation of the sun.
We have the corresponding figure as follows.
So we use trigonometric ratios to find the required angle.
In a triangle ABC
`=> tan theta = (AB/(BC)`
`=> tan theta = h/h`
`=> tan theta = 1
`=> theta = 45^@`
Hence the angle of evevation of sun is 45°
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