For a young adult with normal vision, least distance of distinct vision is (in cm)
For a young adult with normal vision, least distance of distinct vision is (in cm) Correct Answer 25 cm
The correct answer is 25cm.
Key Points
- The minimum distance, at which objects can be seen most distinctly without strain, is called the least distance of distinct vision.
- It is also called the near point of the eye.
- For a young adult with normal vision, the near point is about 25 cm.
- The farthest point up to which the eye can see objects clearly is called the far point of the eye. It is infinity for a normal eye.
Additional Information
- The eye lens is composed of fibrous, jelly-like material. Its curvature is modified by the ciliary muscles.
- The change in the curvature of the eye lens can thus change its focal length.
- When the ciliary muscles are relaxed, the lens becomes thin. Thus, its focal length increases. This enables us to see distant objects clearly.
- On the other hand to see nearby objects, the ciliary muscles contract. This increases the curvature of the eye lens. The eye lens then becomes thicker. thus its focal length decreases and enables us to see nearby objects clearly.
- The ability of the eye lens to adjust its focal length is called accommodation.
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Feb 20, 2025