1 A parallel beam of light is sent through an aquarium iea r
1) A parallel beam of light is sent through an aquarium (i.e.a rectangular box with glass sides, filled with water).
A conves glass lens is held in water. Compared to thebehaviour of the same lens in air, will the lens in water focus thebeam:
a) closer to the lens than in air;
b) at the same position as in air;
c) further from the lens than in air?
(Hint: The magnitude of the refractive index of water isbetween the magnitudes of the refractive indices of the lensmaterial and air)
--
2) The water in the aquarium is replaced by a transparentliquid with refractive index with greater than that of the lens.Will the lens now be a convergent or a divergent lens?Explain.
Thanks.
1) A parallel beam of light is sent through an aquarium (i.e.a rectangular box with glass sides, filled with water).
A conves glass lens is held in water. Compared to thebehaviour of the same lens in air, will the lens in water focus thebeam:
a) closer to the lens than in air;
b) at the same position as in air;
c) further from the lens than in air?
(Hint: The magnitude of the refractive index of water isbetween the magnitudes of the refractive indices of the lensmaterial and air)
--
2) The water in the aquarium is replaced by a transparentliquid with refractive index with greater than that of the lens.Will the lens now be a convergent or a divergent lens?Explain.
Thanks.
Solution
) A parallel beam of light is sent through an aquarium (i.e. arectangular box with glass sides, filled with water).
A convex glass lens is held in water. Compared to the behaviorof the same lens in air, will the lens in water focus thebeam:
a) closer to the lens than in air;
b) at the same position as in air;
c) further from the lens than in air?
(Hint: The magnitude of the refractive index of water isbetween the magnitudes of the refractive indices of the lensmaterial and air)
when the lens is immersed in water
1/f=(/w-1)[1/R1-1/R2]
from this formula when lens is immersed in water whoserefractive index is less than the refractive index of theglass the
when the lens is immersed in water
1/f=(/w-1)[1/R1-1/R2]
from this formula when lens is immersed in water whoserefractive index is less than the refractive index of theglass the
2) The water in the aquarium is replaced by a transparentliquid with refractive index with greater than that of the lens.Will the lens now be a convergent or a divergent lens? Explain.
from the above explanation
focal length will become negative and hence lens will behave asdivergent lens.
from the above explanation
focal length will become negative and hence lens will behave asdivergent lens.
Thanks.