Question

If the ciliary muscles of a normal eye are in their (a) most relaxed state. (b) most contracted state. Mention in brief how focal length and power of eye lens will change in both the cases. Give reason for your answer.

Answer 1

Answer:

• (a), i.e. when ciliary muscles of a normal eye is most relaxed. (b) Reason: When ciliary muscles are relaxed, the eye lens becomes thin. Thus, its focal length increases. In case when ciliary muscles is in most contracted state, radius of curvature of eye lens increases.
• When ciliary muscles are relaxed, the eye lens becomes thin. Thus, its focal length increases. In case when ciliary muscles is in most contracted state, radius of curvature of eye lens increases.
• a) the size of lens is larger thus the focal length is more & the curvature if lens is less. and power is inversely proportional to focal length 
• a) the size of lens is larger thus the focal length is more & the curvature if lens is less. and power is inversely proportional to focal length b) vice versa of (a). the size of lens decreases thus the focal length is less. $\:$