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प्रश्न
Explain why the image distance in the eye does not change when we change the distance of an object from the eye?
उत्तर
The focal length of the human lens can change i.e., increase or decrease, depending on the distance of objects and due to this the image distance in the eye does not change when we change the distance of an object from the eye. It is the ciliary muscles that modifies the curvature of the lens to change its focal length.
For example, to see a distant object clearly, the focal length of the lens should be larger. For this, the ciliary muscles relax to decrease the curvature and thereby increase the focal length of the lens. Hence, the lens becomes thin. This enables the image to be formed on the retina of the human eye.
Now if the same object is moved closer to eye, the ciliary muscles contract to increase the curvature and thereby decrease the focal length of the lens. Hence, the lens becomes thick and we still obtain the image of the object on the retina.
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संबंधित प्रश्न
What is the name of:
the curved, transparent front surface of the eye?
Fill in the following blank with suitable word:
The part of eye which alters the size of the pupil is............
Which part brings the image into sharp focus on the retina? How does it do this?
Name the following:
Short sightedness.
Answer the following question.
Write the structure of eye lens and state the role of ciliary muscles in the human eye.
Give Technical Term:
The fluid which conveys the vibrations of sound in the cochlea and semicircular canals.
State the Function:
Visual purple
Complete the following sentence with appropriate Word
The aperture in the eye through which light enters is the:
Name the following:
The fibres which collectively hold the lens in position.
Write the main functional activity of the following structure.
Ciliary body and suspensory ligament
