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Course: UP Class 12 Physics > Unit 2

Lesson 4: Refraction at spherical surfaces and by lenses
Science
UP Class 12 Physics
Ray optics and optical instruments
Refraction at spherical surfaces and by lenses
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Power of lens

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Problem

Apoorva broke her pair of glasses in a football match, and sees an optician for a new pair. She's prescribed glasses that are convex lenses of focal length 40 cm each.
What is the power of Apoorva's glasses in units of dioptres (D)?
Choose 1 answer:
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Video 11 minutes 48 seconds
Power of lens