Question

A student on the last bench can read the letters written on the blackboard but is not able to read the letters written in his textbook. Which of the following statements is correct?
A) The near point of his eyes has receded away.
B) The near point of his eyes has come closer to him.
C) The far point of his eyes has come closer to him.
D) The far point of his eyes has receded away.

Answer 1

This question can be easily solved by knowing the basic knowledge about the defects of the eye. The different types of defects by which a person can suffer. Here mainly this is based on myopia and hypermetropia.

Complete step by step answer:
Let us analyse the question, as per the question it has mentioned that a student on the last bench can read the letters written on the blackboard clearly but not able to read the letters written in his textbook, it means he can easily see the far away objects clearly but difficult to see nearby objects. It is obvious that this student has some defect of the eye.
Now, let us look into most common defects that occur to human beings and the nature of the defects. Few persons can see objects which are near to them very clearly but could not see the objects which are at far distance. This kind of defect is known as short-sightedness or it is also called myopia. On the other hand, few people can see far away objects clearly but not nearby objects. This kind of defect is known as far-sightedness or hypermetropia. To answer this question, we also must know few terms like near point of eye and far point of eye.
Let us look into these terms first. Near point of eye means the distance at which our eyes can see objects very clearly which is near to eye. The normal near point of the eye is 25 cm. If a person cannot read at this distance clearly means his/her near point has changed. He/she can see all the distances after the near point clearly. A person can get hypermetropia due to the change of near point of eye. Far point means the farthest distance at which person can see objects / letters clearly within the eye’s accommodation. Usually the far point of eye is infinite distance. But we usually consider it as 6 m because the change in the accommodation of the eye is negligible from 6 m to infinite distance. A person is having myopia means the far point of eye has changed.
Now, we conclude that in this given question a student is suffering from hypermetropia or far- sightedness. i.e. he could not read the nearby letters clearly. It means his near point has changed. As the desk is usually at a distance more than 25 cm from the eyes of a person. It is clear that his near point has receded away.

So, the correct answer is “Option A”.

Note:
By the name near-sightedness sometimes we may confuse that near-sightedness means a person cannot read nearby letters clearly. But we remember that near-sighted means we can see nearby objects clearly. In the same way the name far-sighted means we see far away objects very clearly.