An observer 1.5 m tall is 20.5 metres away from a tower 22 metres high. Determine the angle of elevation of the top of the tower from the eye of the observer. - Noon Academy

An observer 1.5 m tall is 20.5 metres away from a tower 22 metres high. Determine the angle of elevation of the top of the tower from the eye of the observer.

ML Agarwal Heights and distances class 10 Maths

An observer 1.5 m tall is 20.5 metres away from a tower 22 metres high. Determine the angle of elevation of the top of the tower from the eye of the observer.

Solution:

In the figure,

AB is the tower and CD is an observer

θ is the angle of observation

It is given that

AB = 22m

CD = 1.5 m

Distance BD = 20.5 m

From the point C construct CE parallel tp DB

AE = 22 – 1.5 = 20.5 m

CE = DB = 20.5 m

tan θ = AE/CE

Substituting the values

tan θ = 20.5/20.5 = 1

tan 45⁰ = 1

θ = 45⁰

i

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