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प्रश्न
Define the term "power of accommodation" of human eye.
उत्तर
The power of accommodation of the human eye refers to the ability of the eye to change the focal length of its lens so as to focus the light from both nearby and distant objects on the retina.
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संबंधित प्रश्न
The human eye can focus objects at different distances by adjusting the focal length of the eye lens. This is due to ______.
A person got his eyes tested by an optician. The prescription for the spectacle lenses to be made reads :
Left eye : +2.50 D
Right eye : +2.00 D
Which lens bends the light rays more strongly?
Name the part of the eye:
which controls the amount of light entering the eye.
Name two types of cells in the retina of an eye which respond to light.
What is the principal function of the eye-lens?
Give the scientific names of the following parts of the eye:
changes shape to focus a picture on the retina.
Fill in the following blank with suitable word:
Most of the refraction of light rays entering the eye occurs at the outer surface of the.............
The eyes of a person are focused (i) on a nearby object, and (ii) on a distant object, turn by turn. In which case:
the focal length of eye-lens will be the maximum?
Explain the functions of the following parts of the eye:
(i) cornea
(ii) iris
(iii) pupil
(iv) ciliary muscles
(v) eye-lens
Refraction of light in the eye occurs at:
(a) the lens only
(b) the cornea only
(c) both the cornea and the lens
(d) the pupil
The term " accommodation" as applied to the eye, refers to its ability to:
(a) control the light intensity falling on the retina
(b) erect the inverted image formed on the retina
(c) vary the focal length of the lens
(d) vary the distance between the lens and retina
The descriptions of five kinds of images are given below:
(a) diminished and virtual
(b) enlarged and real
(c) enlarged and erect
(d) real and inverted
(e) virtual and the same size
Which one of these describes the image formed:
(i) on the retina of the eye?
(ii) by a magnifying glass?
(iii) by a convex driving mirror on a car?
(iv) by a plane mirror?
(v) on the screen of a slide projector?
A person got his eyes tested. The optician's prescription for the spectacles reads:
Left eye: − 3.00 D
Right eye: − 3.50 D
The person is having a defect of vision called:
(a) presbyopia
(b) myopia
(c) astigmatism
(d) hypermetropia
Which of the following have a wider field of view?
(a) Animals having two eyes on the opposite sides of their head.
(b) Animals having two eyes at the front of their head.
Name two animals having eyes:
one the sides of the head.
Among animals, the predators (like lions) have their eyes facing forward at the front of their heads, whereas the animals of prey (like rabbit) usually have eyes at the sides of their head. Why is this so?
Given below is a set of five parts. Rewrite them in correct sequence.
Conjunctiva, retina, cornea, optic nerve, lens.
The figure below compares a part of our eye with a part of a photographic camera.
Name the corresponding parts of the eye the camera shown here that are comparable in function.
Name the following:
White part of the eye.
State the Function:
Conjunctiva
In a relaxed state, the focal length of healthy eyes is _______.
Write the name.
The part of human eye that transmits electrical signals to the brain.
At noon the sun appears white as
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 | Hypermetropoia | e | Power of accomodation |
Name the following:
Capacity of the eye to focus at different distances.
Name the following:
The layer of the wall of the eye-ball that corresponds to the black lining of the box of a camera
An aperture that controls the passage of light into the eye is ______.
Name the following:
Three layers of the eye ball.
