Q17 of 28 Page 93

On observing from the top of a lighthouse 60 m high from the sea level, the angles of depression of two ships are 30° and 45°. If one ship is just behind the other ship on the same side of the lighthouse then find the distance between the ships.


Let BC = g is the height of the lighthose.


Given, Angle of Depression for ship A is 450, for ship B 30o.Height of the lighthouse is 60.


in ABC,


∠CAB = 45o




AB = 60


in CDB,


∠CDB = 30o




BD = 60√3


Distance between the ships = BD – AB


= 60√3 – 60


= 60(√3 – 1)


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