The change in focal length of an eye-lens is caused by the action of the:(a) pupil (b) retina (c) ciliary muscles (d) iris

Academic Physics NCERT Class 10

(c) ciliary muscles

Explanation

Ciliary muscles are circular muscle which changes the focal length or the thickness of the eye-lens while focussing by changing its shape and thereby enable us to see objects that are near or far away.

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Updated on: 10-Oct-2022

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