. A student cannot see clearly a chart hanging on a wall placed at a


(a) A student cannot see clearly a chart hanging on a wall placed at a distance of 3 from his eyes. Name the defect of vision he is suffering from. Draw a ray diagram to illustrate this effect . List its two possible causes

 

(b) Draw a ray diagram to show how this defect may be corrected using a lens apropriate focal length.

 

(c) An eye donation camp is being organised by social workers in your locality. and why would you help in this cause

Best Answer

(a) Myopia is the defect of the eye vision due to which a person can see the near objects clearly, nut he cannot see the far objects clearly.

 

Causes of myopia. Myopia is caused

 

-due to the elongation of the eye ball.

 

-due to decrease in the focal length of the eye lens. The eye lens becomes more convergent myopia can be corrected by using a concave lens of suitable focal length in the  spectacles of such a person.

 

(b)

 

Ray diagram to illustrate this defect  Ray diagram to show the correction of myopia

 

convergent myopia can be corrected by using a concave

 

Ray diagram to illustrate this defect   Ray

 

 

(c) There are millions of blind people in our country who cannot see at all. The eyesight of most these blind people can be restored if they .are given the eyes donated by other persons after then death.• Our two eyes can give eyesight to two blind persons

 

In the eye donation camps, we can even today, make a pledge in writing ,i.e., whenever we dir

 

our eyes should be removed and given to the blind persons to light up their dark world. We should be greatful to God that he has given us the gift of vision to see this . wonder world .We must try and pass on this priceless gift of vision to our less fortunate blind brat and sisters by registering our name for eye donation

 

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