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Question
A boy is 1.54 m tall. Standing at a distance of 3m in front of a 4.54 m high wall he can just manage to see the sun. Find the angle of elevation of the sun.
Solution
Let the position of the boy be at point T and P be the position of the sun.
BR = TQ = 3m
PQ = 4.54 m
BT = 1.54 m
.·.PR = 4.54 m - 1.54 m = 3 m
In ΔPRB
`"PR"/"BR" = tan θ`
`3/3 = tan θ`
tan θ = 1
We know that tan 45° = 1.
Thus, the angle of elevation is θ = 45°.
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