Question

a man is sitting in the middle of a backyard observing a flying bird in the North at an angle of elevation of 30° and after 1 minute he sees the same bird in the south at an angle of elevation 60° if the bird flies all along a straight line at the height of 50 square root of 3 then its speed is

Answer 1

The speed of the bird is 3.33 m/s

Step-by-step explanation:

Height = AE = 50√3 m

In ΔADE, we have,

tan 60 = ED/(50√3)

√3 = ED/(50√3)

∴ ED = 50 × 3  = 150 m

In ΔAEF, we have,

tan 30 = FE/(50√3)

1/√3 = FE/(50√3)

∴ FE = 50 m

The distance traveled by the bird is:

D = FE + ED = 50 + 150 = 200 m

The time taken by the bird to travel is:

T = 1 minute = 60 seconds

The speed is given by the formula:

Speed = D/T = 200/60

∴ Speed = 3.33 m/s