Geometrical OpticsHard
Question
A fish rising vertically up towards the surface of water with speed 3 ms-1 observes a bird diving vertically down towards it with speed 9 ms-1. The actual velocity of bird is
Options
A.4.5 ms-1
B.5 ms-1
C.3.0 ms-1
D.3.4 ms-1
Solution
Here optical distance between fish and the bird is s = y′ + μy
Differentiating w.r.t t we get
⇒ 9 = 3 +
⇒ 
= 4.5 m/sec
Differentiating w.r.t t we get
⇒ 9 = 3 +
⇒ = 4.5 m/secCreate a free account to view solution
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