A bird is sitting on the top of a vertical pole 20m high and its elevation from a point O on the ground is 45∘ , it flies off horizontally straight away from the point O. After one second, the elevation of the bird from O is reduced to 30∘ , then the speed (in m/s) of the bird isA.40(2–√−1)B.40(3–√−2–√)C.202–√D.20(3–√−1)

Harshit Singh , 2 Years ago

Grade 12th pass