The angle of elevation of a jet plane from a point A on the ground is 60 . After a flight of 15 seconds, the angle of elevation changes to 30 . If the jet plane is flying at a constant height of 1500√3 m find the speed of the jet plane.
Let P and Q be the two positions of the plane and let A be the point of observation. Let ABC be the horizontal line through A. It is given that angles of elevation of the plane in two positions P and Q from a point A are 60 and 30, respectively.
