JEE Mains · Physics · STD 12 - 9. Ray optics and optical instruments
A fish rising vertically upward with a uniform velocity of \(8\,ms ^{-1}\), observes that a bird is diving vertically downward towards the fish with the velocity of \(12\,ms ^{-1}\). If the refractive index of water is \(\frac{4}{3}\), then the actual velocity of the diving bird to pick the fish, will be \(.......\,ms ^{-1}\).
- A \(6\)
- B \(9\)
- C \(3\)
- D \(12\)
Answer & Solution
Correct Answer
(C) \(3\)
Step-by-step Solution
Detailed explanation
\(\frac{V_{ b / f }}{\frac{4}{3}}=\frac{-8}{\frac{4}{3}}+\frac{(- v )}{1}\) \(\Rightarrow \frac{-12}{\frac{4}{3}}=\frac{-8}{\frac{4}{3}}+\frac{(- v )}{1}\) \(\Rightarrow v =3\,m / s\)
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