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Question
Nearsightedness: elongated eyeball : : farsightedness: _______
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Solution
Nearsightedness: elongated eyeball : : farsightedness: flattening of eye ball
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RELATED QUESTIONS
Millions of people in the developing countries of the world are suffering from corneal blindness. These persons can be cured by replacing the defective cornea with the cornea of a donated eye. A charitable society of your city has organised a campaign in your neighbourhood in order to create awareness about this fact. If you are asked to participate in this mission, how would you contribute in this noble cause?
(i) State the objective of organising such campaigns.
(ii) List two arguments which you would give to motivate the people to donate their eyes after death.
(iii) List two values which are developed in the persons who actively participate and contribute in such programmes.
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by using a concave lens?
Which defect of vision can be rectified:
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Name the defect of vision which makes the eye-lens cloudy resulting in blurred vision.
What is the other name of old age hypermetropia?
Name one defect of vision (or eye) which cannot be corrected by any type of spectacle lenses.
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A man can read the number of a distant but clearly but he finds difficulty in reading a book.
What type of spectacle lens should he use to correct the defect?
A student sitting in the last row of the class-room is not able to read clearly the writing on the blackboard.
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What are the two most common defects of vision (or defects of eye)? How are they corrected?
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By closing the eyes and gently pressing them by your palms, you may see some specks of brilliant light. How do you get this sensation while there is no light entering your eyes?
A person cannot read newspaper placed nearer than 50 cm from his eyes. Name the defect of vision he is suffering from. Draw a ray diagram to illustrate this defect. List its two possible causes. Draw a ray diagram to show how this defect may be corrected using a lens of appropriate focal length.
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:
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Give Reason:
Why do we see clearly in the central region of the retina?
Complete the following sentence with appropriate word :
An inability to focus on nearby objects due to loss of elasticity of the lens with age is called Iris.
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(i) Identify the defect shown in the diagram.
(ii) Give two possible reasons for the above defect.
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Nearsightedness : concave lens : : farsightedness : _______
What are the causes of ‘Myopia’?
Which of the following statement is correct?
A student sitting at the back of the classroom cannot read clearly the letters written on the blackboard. What advice will a doctor give to her? Draw ray diagram for the correction of this defect.
Given alongside is a diagram depicting a defect of the human eye. Study the same and answer the questions that follow:
 |
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- Name the parts labelled 1 to 4.
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