Advertisements
Advertisements
Question
You do not enjoy watching a movie from a very short distance from the screen in a cinema hall. Why?
Advertisements
Solution
Our eyes are designed to focus at a great variety of distances. To focus constantly at a short distance can make the lens focusing muscles fatigued. Therefore, we do not enjoy watching a movie from a very short distance from the screen in cinema hall.
RELATED QUESTIONS
A man can read the number of a distant but clearly but he finds difficulty in reading a book.
From which defect of the eye is he suffering?
What are the two most common defects of vision (or defects of eye)? How are they corrected?
The defect of vision in which the eye-lens of a person gets progressively cloudy resulting in blurred vision is called:
(a) myopia
(b) presbyopia
(c) colourblindness
(d) cataract
State the main functions of the following:
Tears
List two causes of presbyopia. Draw labelled diagram of a lens used for the correction of this defect of vision.
Explain the Term: Astigmatism
Give Technical Term:
The path which responsible for protecting the eye from sweat.
Given below is a diagrammatic representation of a defect of the human eye:

(i) Identify the defect.
(ii) Mention two reasons for the above defect.
(iii) State how the defect can be rectified.
(iv) Name the part of the eye responsible for maintaining the shape of the eyeball.
A person needs a lens of power –4.5 D for correction of her vision.
- What kind of defect in vision is she suffering from?
- What is the focal length of the corrective lens?
- What is the nature of the corrective lens?
