The angle of elevation of an aeroplane from a point on the ground is 60o. After flying for 30 seconds, the angle of elevation changes to 30o. If the aeroplane is flying at a height of 4500 m, then what is the speed (in m/s) of aeroplane?
Show answer & explanation
Correct answer: B
Explanation
The correct answer is option 2. i.e. 100√3
√3 unit = 4500 m
2 unit = 3000 √3 m
Speed of the airplane = 
= 100√3