1. A student has difficulty in reading the blackboard while sitting in the last row. It shows that he is unable to see distant objects clearly. He is suffering from myopia. This defect can be corrected by using a concave lens. For more answers visit to website: https://www.tiwariacademy.com/ncert-solutRead more

    A student has difficulty in reading the blackboard while sitting in the last row. It shows
    that he is unable to see distant objects clearly. He is suffering from myopia. This defect
    can be corrected by using a concave lens.

    For more answers visit to website:
    https://www.tiwariacademy.com/ncert-solutions/class-10/science/chapter-11/

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  2. The near point of the eye is the minimum distance of the object from the eye, which can be seen distinctly without strain. For a normal human eye, this distance is 25 cm. The far point of the eye is the maximum distance to which the eye can see the objects clearly. The far point of the normal humanRead more

    The near point of the eye is the minimum distance of the object from the eye, which can
    be seen distinctly without strain. For a normal human eye, this distance is 25 cm. The far
    point of the eye is the maximum distance to which the eye can see the objects clearly.
    The far point of the normal human eye is infinity.

    For more answers visit to website:
    https://www.tiwariacademy.com/ncert-solutions/class-10/science/chapter-11/

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  3. The person is able to see nearby objects clearly, but he is unable to see objects beyond 1.2 m. This happens because the image of an object beyond 1.2 m is formed in front of the retina and not at the retina, as shown in the given figure. To correct this defect of vision, he must use a concave lens.Read more

    The person is able to see nearby objects clearly, but he is unable to see objects beyond
    1.2 m. This happens because the image of an object beyond 1.2 m is formed in front of
    the retina and not at the retina, as shown in the given figure.
    To correct this defect of vision, he must use a concave lens. The concave le ns will bring
    the image back to the retina as shown in the given figure.

    For more answers visit to website:
    https://www.tiwariacademy.com/ncert-solutions/class-10/science/chapter-11/

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  4. When the ciliary muscles are relaxed, the eye lens becomes thin, the focal length increases, and the distant objects are clearly visible to the eyes. To see the nearby objects clearly, the ciliary muscles contract making the eye lens thicker. Thus, the focal length of the eye lens decreases and theRead more

    When the ciliary muscles are relaxed, the eye lens becomes thin, the focal length
    increases, and the distant objects are clearly visible to the eyes. To see the nearby objects
    clearly, the ciliary muscles contract making the eye lens thicker. Thus, the focal length of
    the eye lens decreases and the nearby objects become visible to the eyes. Hence, the
    human eye lens is able to adjust its focal length to view both distant and nearby objects
    on the retina. This ability is called the power of accommodation of the eyes.

    For more answers visit to website:
    https://www.tiwariacademy.com/ncert-solutions/class-10/science/chapter-11/

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  5. The sky appears dark instead of blue to an astronaut because there is no atmosphere in the outer space that can scatter the sunlight. As the sunlight is not scattered, no scattered light reach the eyes of the astronauts and the sky appears black to them. For more answers visit to website: https://wwRead more

    The sky appears dark instead of blue to an astronaut because there is no atmosphere in the outer space that can scatter the sunlight.
    As the sunlight is not scattered, no scattered light reach the eyes of the astronauts and the sky appears black to them.

    For more answers visit to website:
    https://www.tiwariacademy.com/ncert-solutions/class-10/science/chapter-11/

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