Page 1 - Lesson note refraction through concave lens

SAI INTERNATIONAL SCHOOL
PHYSICS
CLASS X
Chapter: LIGHT(REFLECTION & REFRACTION)
MODULE-31

LESSON NOTES: refraction through concave lens

o Nature, position and relative size of the image formed by a concave
lens for various positions of the object is given below in the table

Position of the Position of the Relative size of Nature of
object image the image the image

Highly
At infinity At focus F diminished, point- Virtual and
erect
sized

Between infinity and Between F 1 and Virtual and
optical center O of the optical center O Diminished erect
lens

o A concave lens will always give a virtual, erect and diminished image,
irrespective of the position of the object.

Image Formation in Lenses Using Ray Diagrams
o Ray diagram helps us to study the nature, position and relative size of
the image formed by lenses.
o For drawing ray diagrams we first consider how light rays falling on
both concave and convex lens in three different ways get refracted.

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