question_answer

The angle of elevation of a jet plane from a point P on the ground is \[60{}^\circ \]. After 15 second of flight the angle becomes \[30{}^\circ \]. If the height of the jet plane is 1500 m, then find the speed of the jet plane.

A)  \[300\,m/s\]                  

B)  \[400\sqrt{3}\,m/s\]

C)  \[150\,m/s\]                  

D)  \[200/\sqrt{3}\,m/s\]

E)  None of these