Question

angle of elevation of a jet plane from the point a on the ground is 60° after flight of 15 sec the angle of elevation changes to 30° if the jet plane is flying with the constant height 1500√3 meter find the speed of the jet

Answer 1

Answer:

In triangle ABC,

tan60=BC/AB=3600*3(1/2)

AB=BC/tan60=3600*3^(1/2)/3^(1/2)

AB=3600

In triangle ADE,

tan30= DE/AD

AD=DE/tan30=3600*3^(1/2)/(1/3^(1/2))

AD=3600*3

AD=10800

The distance traveled by the jet plane=AD-AB=10800-3600=7200

So, the speed of the jet plane=7200/30=240

Therefore, the speed of the jet plane is 240 m/s.