Physics
Grade-10
Easy
Question
A convex lens in a magnifying glass can be used to focus the Sun’s light rays onto a paper, which lights up a fire after some time. What would happen if the magnifying glass were replaced with a concave lens?
- The light rays would not concentrate
- There will not be a fire
- There will not be a bright spot obtained on the paper
- All of these
Hint:
Concave lenses is a diverging/ separating lens which will show deviations from a convex lens.
The correct answer is: All of these
All of these would happen if the magnifying glass were replaced with a concave lens.
- When the convex lens in a magnifying glass were replaced by a concave lens, the rays won't get focused or concentrated.
- Since the concave lens, separates/diverges the light rays, the light rays would not concentrate.
- As the light rays would not concentrate there will not be any bright spot on the paper and this will lead to formation of no fire or burning of paper.
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