Optics 7 Question 33

34. Water (with refractive index =43 ) in a tank is 18cm deep. Oil of refractive index 74 lies on water making a convex surface of radius of curvature R=6cm as shown. Consider oil to act as a thin lens. An object S is placed 24cm above water surface. The location of its image is at xcm above the bottom of the tank. Then x is.

(2011)

s.

Show Answer

Solution:

Two refractions will take place, first from spherical surface and the other from the plane surface.

So, applying

μ2vμ1u=μ2μ1R

two times with proper sign convention.

Ray of light is travelling downwards. Therefore, downward direction is taken as positive direction.

7/4v1.024=7/41.0+64/3(18x)7/4v=4/37/4

Solving these equations, we get, x=2cm

Answer is 2 .



जेईई के लिए मॉक टेस्ट

एनसीईआरटी अध्याय वीडियो समाधान

दोहरा फलक