Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
JIPMER 2016
Exam
JIPMER
Year
2016
Subject
Physics
Chapter
Ray Optics

JIPMER 2016 · Physics · Ray Optics

A fish rising vertically to the surface of water in a lake...

A fish rising vertically to the surface of water in a lake uniformly at the rate of 2 m/s2 \mathrm{~m} / \mathrm{s} observes a kingfisher diving vertically towards the water at a rate of 10 m/s10 \mathrm{~m} / \mathrm{s}. If refractive index of water n=43n=\frac{4}{3}, what will be the actual velocity of the kingfisherA fish rising vertically to the surface of water in a lake uniformly at the rate of 2 ~m / s observes a kingfisher

Options

  1. A10 m/s10 \mathrm{~m} / \mathrm{s}
  2. B8 m/s8 \mathrm{~m} / \mathrm{s}
  3. C6 m/s6 \mathrm{~m} / \mathrm{s}
  4. D9 m/s9 \mathrm{~m} / \mathrm{s}

Correct answer

C. 6 m/s6 \mathrm{~m} / \mathrm{s}

Step-by-step solution

A fish rising vertically to the surface of water in a lake uniformly at the rate of 2 ~m / s observes a kingfisher ∵\because Velocity of bird w.r.t. fish, vB→F=10 m/sv_{B \rightarrow F}=10 \mathrm{~m} / \mathrm{s} and velocity of fish w.r.t. ground VF→G=2 m/s∴V_{F \rightarrow G}=2 \mathrm{~m} / \mathrm{s} \therefore Distance between bird and fish, as seen by fish S=x+nyS=x+n y on differentiating w.r.t. time, we get dSdt=dxdt+ndydtvB→F=vF→G+n⋅vB→G⇒10=2+43vB→G⇒vB→G=84/3=6 m/s\begin{aligned} & \frac{d S}{d t}=\frac{d x}{d t}+n \frac{d y}{d t} \\ & v_{B \rightarrow F}=v_{F \rightarrow G}+n \cdot v_{B \rightarrow G} \\ & \Rightarrow \quad 10=2+\frac{4}{3} v_{B \rightarrow G} \\ & \Rightarrow \quad v_{B \rightarrow G}=\frac{8}{4 / 3}=6 \mathrm{~m} / \mathrm{s} \\ & \end{aligned}
Practice Ray Optics on Quantrex Academy →

More from Ray Optics

A container is filled with water (μ = 4/3 ) up to a height of 24 cm. A concave mirror is… MHT CET Medical 2026The refracting angle of a prism is 'A' and its refractive index is ((A)/(2)). The minimum… MHT CET Medical 2026A circular beam of light having diameter 'd' falls on a plane liquid surface from air.… MHT CET Medical 2026What is the total optical path length of two media in contact with thicknesses of d and… MHT CET Medical 2026A beam of white light is allowed to pass through convex lens parallel to principal axis… MHT CET Medical 2026The angle of minimum deviation produced by a thin prism in air is δ_1 . What will be the… MHT CET Medical 2026A ray of light passes through four transparent media with refractive indices μ_1 , μ_2… MHT CET Medical 2026The thin prism having refracting angle 10^ ^ ∘ is made of glass of refractive index 1.42… MHT CET Medical 2026 Full Ray Optics list All JIPMER PYQs