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प्रश्न
A normal eye is not able to see objects closer than 25 cm because
पर्याय
the focal length of the eye is 25 cm
the distance of the retina from the eye-lens is 25 cm
the eye is not able to decrease the distance between the eye-lens and the retina beyond a limit
the eye is not able to decrease the focal length beyond a limit.
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उत्तर
the eye is not able to decrease the focal length beyond a limit
The ciliary muscles adjust the focal length to form an image on the retina, but the muscles cannot be strained beyond a limit. Hence, if the object is brought too close to the eye, the focal length cannot be adjusted to form the image on the retina.
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संबंधित प्रश्न
The lens mentioned in 6(b) above is of focal length 25cm. Calculate the power of the lens.
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1) Which lenses are used in her spectacles?
2) State the defect of vision Kavita is suffering from.
3) Find the focal length of the lenses used in her spectacles
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(b) state the nature of lens Y.
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(b) What is the power of lens A and lens B?
(c) What is the power of combination if lenses A and B are held close together?
Name the type of lens whose power is positive.
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(i) Name the Lens LL’.
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(iii) State three characteristics of the image.
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