Given Below is a Diagram Showing a Defect of Human Eye. Study It And Answer the Following Questions. - Science and Technology 1

Advertisements
Advertisements

Given below is a diagram showing a defect of human eye. Study it and answer the following questions.

(i) Name the defect shown in the figure.
(ii) Give reason for this defect of eye in human being.
(iii) Name the type of lens used to correct the eye defect.

Advertisements

Solution

(i) The defect shown in the figure is hypermetropia or long-sightedness.
(ii) Two possible reasons are
     a) Ciliary muscles have become weak, so the converging power of the eye lens decreases.
     b) Because of shortening of the eye ball or flattening of the eye lens.
(iii) To correct the eye defect, a suitable convex lens is used.

  Is there an error in this question or solution?
2013-2014 (March)

RELATED QUESTIONS

In a Std. X class out of 40 students 10 students use spectacles, 2 students have positive power and 8 students have negative power of lenses in their spectacles.

Answer the following questions:

(1) What does the negative power indicate?

(2) What does the positive power indicate?

(3) Generally which type of spectacles do most of the students use?

(4) What defect of eyesight do most of the students suffer from?

(5) Give two possible reasons for the above defect.


What is myopia?


Explain two possible reasons of myopia. How can it be corrected? Explain with a suitable diagram.


the biological/technical terms for the lens of eye losing flexibility resulting in a kind of long-sightedness in middle aged people.


What is the other name of old age hypermetropia?


What is the far point of a person suffering from myopia (or short-sightedness)?


Your friend can read a book perfectly well but cannot read the writing on blackboard unless she sits on the front row in class. 

 Is she short-sighted or long-sighted?


Differentiate between myopia and hypermetropia. What type of spectacles should be worn by a person having the defects of myopia as well as hypermetropia? How does it help?


What is short-sightedness? State the two causes of short-sightedness (or myopia). With the help of ray diagrams, show:
(i) the eye-defect short-sightedness.
(ii) correction of short-sightedness by using a lens.


The defect of vision which cannot be corrected by using spectacles is:
(a) myopia
(b) presbyopia
(c) cataract
(d) hypermetropia


To read a book held at a distance of 25 cm, will she need converging or diverging spectacle lenses?


A person can read a book clearly only if he holds it at an arm's length from him. Name the defect of vision:  

if the person is a young man 


Differentiate between members of the following pair with reference to what is asked in bracket.

Rods and cones (sensitivity)


Name an old age eye defect. What happens in it?


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?


Enumerate the common defects of vision, their causes and the possible methods of correcting them.


Given below is a diagram depicting a defect of the human eye. Study the same and answer the question that follow:

Name the defect shown in the diagram.


Observer the following diagram and answer the questions.
a) Which eye defect is shown in this diagram?
b) What are the possible reasons for this eye defect?
c) How this defect is corrected, write it in brief?


Write whether the following is true or false:
A convex lens is used for correcting myopia.


Why does one feel blinded for a short while on coming out of a dark room?

Given below is a diagram depicting a defect of the human eye? Study the same and answer the question that follow:

Give two possible reasons for this defect of the eye in human beings.


Given below is a diagram depicting a defect of the human eye? Study the same and answer the question that follow:

Draw a labeled diagram to show how the above mentioned defect is rectified using the lens named above.


Have a look at the posture of this woman who is reading a book and answer the questions which follow:

What are the two conditions shown in sections A and B of the eye as applicable to her?


Rewrite the following table so as to match second and third column with first column.

 

Column I
Column II
Column III
(i) Myopia
Old age problem
Bifocal lens
(ii) Presbyopia
Nearsightedness
Concave lens.

Anuja cannot see the blackboard writing but she can see nearby things.
(a) What is the eye defect she is suffering from?
(b) State the possible reason for her defect.
(c) How is it corrected


Solve the following question:
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 an old age eye defect. Why is it caused?


Draw a neat labeled diagram to show how hypermetropia can be rectified.


Explain the Term: Cataract


Name the following:
The defect of the human eye caused due to the uneven surface of the cornea.


Give Technical Term:
The path which responsible for protecting the eye from sweat.


Give Technical Term:
The type of lens used to correct myopia is


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.


Mention, if the following statement is True or False
Hypermetropia is a defect of the eye caused due to the eyeball elongation


In Myopia the human eye _______.


Due to elongation of _______ and increase in curvature of the eye lens, a person cannot see distant objects clearly.


Nearsightedness: elongated eyeball : : farsightedness: _______


Nearsightedness : concave lens : : farsightedness : _______


Write scientific reason.

Nearsightedness, this defect can be corrected by using spectacles with concave lens.


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.


What are the causes of ‘Myopia’?


Differentiate the eye defects: Myopia and Hypermetropia


Myopia and hypermetropia can be corrected by:


Correlate the given sequence:

Hypermetropia : Convex lens : ______ : Concave lens


Observe the figure whether it is correct or not and explain the phenomenon.


Observe the figure and answer the following questions: 

  1. Name the defect of vision represented in the above figure.
  2. State the reasons for this defect.
  3. How is it corrected?
  4. Draw the diagram to show the correction of this defect.

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. Hypermetropia e. Power of accommodation

Complete the following table by observing the given figure:

Figure →
Points ↓
(a) Name of the defect ____________ ____________
(b) Position of the image ____________ ____________
(c) Lens used to correct the defect ____________ ____________

Share
Notifications



      Forgot password?
Use app×