Question

A bird is sitting on the top of a 80m high tree . from a point on the ground, the angle of elevation of the bird is 45°. the bird flies away horizontally in such a way that it remained at a constant height from the ground. after 2 secs, the angle of elevation of the bird from the same point is 30°. find the speed of flying of the bird ( use√3=1.732)

Answer 1

the speed is 40(root3-1) ms-1

Answer 2

the initial distance:80/tan(45)=80m

the final distance: 80/tan(30)=80/(1/root3)=80*root3m

the speed: (80*root3 -80)/2=29.28m/s