Q16 of 28 Page 93

The shadow of a tower standing on a plane ground becomes 40 m longer when the angle of elevation of the Sun becomes 30° after reduction from 60°. Find the height of the tower.


Let Height of the tower is BC = g.


Given, ∠CAB = 30o∠CDB = 60o AD = 40.


in ∆CAB,




……….(1)


in ∆CDB,




……….(2)


Equation (1) – Equation(2)







120 = 2g√3



(Rationalization)


g = 20√3


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