Ray Optics · JEE Main previous year questions

2005 2 questions

1. Q1312005 · 28 Apr 2005 · Shift 1

   A fish looking up through the water sees the outside world contained in a circular horizon. If the refractive index of water is $\frac{4}{3}$ and the fish is $12\mathrm{cm}$ below the surface, the radius of this circle in $\mathrm{cm}$ is

   1. A.$\frac{36}{\sqrt{7}}$
   2. B.$36\sqrt{7}$
   3. C.$4\sqrt{5}$
   4. D.$36\sqrt{5}$
   Show answer

   Answer: A

2. Q1332005 · 28 Apr 2005 · Shift 1

   A thin glass (refractive index 1.5) lens has optical power of $-5D$ in air. Its optical power in a liquid medium with refractive index 1.6 will be

   1. A.$-1D$
   2. B.$1D$
   3. C.$-25D$
   4. D.$25D$
   Show answer

   Answer: B