MCQ
In optical instruments, the lenses are used to form images by:
- AReflection
- ✓Refraction
- CDispersion
- DScattering
✓
Answer
Correct option: B.
Refraction
A lens is a piece of glass $($plastic$)$ with two refracting surfaces, which are either curved $($e.g., a segment of a sphere$)$ or plain.
Lenses are used to form images by refraction in optical instruments $($microscopes, telescopes, cameras, etc.$)$
There are two types of lenses: converging $($thickest in the middle$)$ and diverging $($thickest at the edges$)$.
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