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प्रश्न
What is the far point of a person suffering from myopia (or short-sightedness)?
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उत्तर
The far point of a person suffering from myopia is located closer than infinity.
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संबंधित प्रश्न
What is myopia?
What is the far point and near point of the human eye with normal vision?
A student suffering from myopia is not able to see distinctly the objects placed beyond 5 m. List two possible reasons due to which this defect of vision may have arisen. With the help of ray diagrams, explain
(i) why the student is unable to see distinctly the objects placed beyond 5 m from his eyes.
(ii) the type of the corrective lens used to restore proper vision and how this defect is corrected by the use of this lens.
(b) If, in this case, the numerical value of the focal length of the corrective lens is 5 m, find the power of the lens as per the new Cartesian sign convention
Explain two possible reasons of myopia. How can it be corrected? Explain with a suitable diagram.
Which defect of vision can be rectified:
by using a concave lens?
Differentiate between myopia and hypermetropia.
The near-point of a person suffering from hypermetropia is at 50 cm from his eye. What is the nature and power of the lens needed to correct this defect? (Assume that the near-point of the normal eye is 25 cm).
What is long-sightedness? State the two causes of long-sightedness (or hypermetropia). With the help of ray diagrams, show:
(i) the eye-defect long-sightedness.
(ii) correction of long-sightedness by using a lens.
Enumerate the common defects of vision, their causes and the possible methods of correcting them.
What eye defect is hypermetropia? Describe with a ray diagram how this defect of vision can be corrected by using an appropriate lens.
Name the following:
The photosensitive pigment present in the rod cells of the retina.
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?
Give Reason:
Older people require glasses to read and write.
Nearsightedness : concave lens : : farsightedness : _______
Observe the given below the figure, correct it and explain and write about the concept depicted in this figure.
Given below is a diagram showing a defect of vision. Name the defect of vision and draw an accurately labelled diagram to correct this defect.
Assertion: Myopia is the defect of vision in which a person cannot see distant objects clearly.
Reason: This due to eye-ball being too short.
Correlate the given sequence:
Hypermetropia : Convex lens : ______ : Concave lens
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?
