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प्रश्न
Boojho while waving his hand very fast in front of his eyes, observes that his fingers appear blurred. What could be the reason for it?
उत्तर
The impression of an image persists for about 1/16th of a second on the retina. This is known as persistence of vision. If still images of a moving object are flashed on the eye at a rate faster than 16 per second, then the eye perceives this object as moving.
So, in case by waving hand very fast in front of eyes, the rate of movement of hand becomes very large (much faster than 16 per second), therefore, the fingers appear blurred.
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संबंधित प्रश्न
Define the term.
Power of accommodation of the eye.
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when the eye is focused on a distant object?
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yellow spot of the retina is the region of colour vision
Write the name.
The part of human eye that transmits electrical signals to the brain.
Write an Explanation.
Minimum distance of distinct vision
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Match the following:
| Column - I | Column - II |
| 1. Retina | a) Path way of light |
| 2. Pupil | b) Far point comes closer |
| 3. Ciliary muscles | c) near point moves away |
| 4. Myopia | d) Screen of the eye |
| 5. Hypermetropia | e) Power of accommodation |
Match the following:
| Column - I | Column - II | ||
| 1 | Retina | a | pathway of light |
| 2 | Pupil | b |
far point comes closer |
| 3 | Ciliary muscles | c |
near point moves away |
| 4 | Myopia | d | screen of the eye |
| 5 | Hypermetropia | e | power of accommodation |
