Advertisements
Advertisements
प्रश्न
A student is unable to see clearly the words written on the black board placed at a distance of approximately 3 m from him. Name the defect of vision the boy is suffering from. State the possible causes of this defect and explain the method of correcting it.
Advertisements
उत्तर
The boy is suffering from nearsightedness i.e. Myopia. The possible causes for this defect are Elongation of the eyeball.
Excessive curvature of the eye lens
This defect can be corrected by placing a concave lens in front of the eye.

APPEARS IN
संबंधित प्रश्न
What is the far point and near point of the human eye with normal vision?
A young man has to hold a book at arm's length to be able to read it clearly. The defect of vision is:
(a) astigmatism
(b) myopia
(c) presbyopia
(d) hypermetropia
A person is unable to read a book placed closer than 1 meter from his eyes. Identify the defect of vision in his eyes. Draw the ray diagrams to show the defect of vision and its correction.
What is Hypermetropia (far sightedness)?
The near point of the eye of a person is 50 cm. Find the nature and power of the corrective lens required by the person to enable him to see clearly the objects placed at 25 cm from the eye?
Name the following:
The defect of the human eye caused due to the uneven surface of the cornea.
Nearsightedness: elongated eyeball : : farsightedness: _______
Observe the figure whether it is correct or not and explain the phenomenon.

A teacher drew the diagram of the heart on the blackboard and told the students to copy it in their notebooks. Mahesh couldn't see the diagram clearly as it appeared blurred to him.
- Name the defect of the eye Mahesh is suffering from.
- Where is the image formed in this defect?
- Mahesh consults an eye doctor and is prescribed suitable lenses to correct the defect. Which type of lens do his spectacles have?
Name the following:
Two kinds of accomodations.
