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प्रश्न
Differentiate the eye defects: Myopia and Hypermetropia
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उत्तर
| Myopia | Hypermetropia |
| Myopia, also known as short-sightedness, occurs due to the lengthening of the eyeball. | Hypermetropia, also known as long-sightedness, occurs due to the shortening of the eyeball. |
| With this defect, nearby objects can be seen clearly but distant objects cannot be seen clearly. | With this defect, distant objects can be seen clearly but nearby objects cannot be seen clearly. |
| The focal length of the eye lens is reduced or the distance between the eye lens and retina increases. | The focal length of the eye lens is increased or the distance between the eye lens and retina decreases. |
| The far point will not be infinity for such eyes and the far point has come closer. | Hence, the near point will not be at 25 cm for such eyes and the near point has moved farther. |
| Due to this, the image of distant objects is formed before the retina. | Due to this, the image of nearby objects is formed behind the retina. |
| This defect can be corrected using a concave lens | This defect can be corrected using a convex lens. |
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संबंधित प्रश्न
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Choose the correct answer :
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Give Reason:
When you enter into a dark room from bright because of sunlight, you can not see things for a few seconds.
Observe the given below the figure, correct it and explain and write about the concept depicted in this figure.
Complete the following table by observing the given figures:
| Figure → |  |
 |
| Points ↓ | ||
| (a) Name of the defect | ______ | ______ |
| (b) Position of the image | ______ | ______ |
| (c) Lens used to correct the defect | ______ | ______ |
