Question

the angle of elevation of a plane from a point on the ground is 60°. After 10 seconds the angle of elevation changes to 30° The plane is flying horizontally at a constant height of
$1500 \sqrt{3}$
Find the plane's speed​

Answer 1

Answer:

Speed = 300 Meters per seconds   or  1080 Km Per Hour

Step-by-step explanation:

H= 1500 Root 3

Two triangles are formed with H as perpendicular.

1. first with 60 Degrees inclination : base = H / Tan60 = 1500 Root3/root3= 1500 m

Initial ground position is 1500 M

2. Second with 30 degree Inclination : base = H/ Tan 30 = 1500. root 3. root 3= 1500x3= 4500 meter

so Horizontal distance in 10 second = 4500-1500 = 3000 meters

Speed = 3000 m/ 10 sec

Speed = 300 Meters per seconds