Explain the power of accommodation of the eye. Draw a ray diagram for image formation by a convex lens when (a) the object is at a distance of 2f, (b) the object is in between 2f and infinity.
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The focal length of the eye's lens changes as it accommodates for near or far vision, allowing clear images to form on the retina.
The power of accommodation refers to the ability of the eye to focus on objects at varying distances by changing the shape of the eye's lens. The eye can adjust its focus from distant objects to near objects through this accommodation process. The ciliary muscles control the shape of the lens to adjust the focal length, allowing the eye to focus on both near and far objects.
Ray Diagrams for Convex Lens:
1. When the object is at a distance of 2f:
For this case, the image formed by a convex lens will be real, inverted, and of the same size as the object. The image is formed at a distance of 2f.
2. When the object is between 2f and infinity:
In this case, the image formed is real, inverted, and diminished in size. The image position lies between f and 2f. Conclusion:
1. Power of accommodation: The ability of the eye to focus on objects at different distances by changing the shape of the lens.
2. Convex lens ray diagrams:
- When the object is at 2f, the image is real, inverted, and of the same size.
- When the object is between 2f and infinity, the image is real, inverted, and diminished.
