Questions & Answers

Which of the following materials cannot be used to make a lens?
A. Water
B. Glass
C. Plastic
D. Clay

Answer Verified Verified
Hint: To get this problem correct you need to think that we can make lenses only of that material which can be transparent. Considering this will solve your problem.

Complete step-by-step answer:
We can say that a lens is an optical device which is transparent and used to focus or disperse the light beam with the help of refraction. A single piece of transparent glass is a simple lens while a compound lens consists of multiple glass and is differently arranged on a common axis.
We can make a lens of water because it is transparent generally and has a different refractive index.
We can also make lenses of glass because they are transparent and have different refractive index. Generally most of the lenses are made of glass almost all.
If we try we can also make lenses prom plastic after making it transparent since plastic can be made transparent and can be constructed into a lens.
With clay it is impossible to make lenses as it is completely opaque and we also cannot make any material of clay which is transparent in nature.
So, we cannot make lenses with clay.
So, the correct option is D.

Note – In order to get this problem solved we just need to know that we can make lenses only with those materials which are transparent and through which light can pass. There are some plastics which are transparent so the plastic can be used to make a lens but the clay is totally an opaque material so the light actually cannot transmit through the clay so clay cannot be used for making the lens.