Q. 155.0( 1 Vote )

A magnifying glass is used, as the object to be viewed can be brought closer to the eye than the normal near point. This results in
A. a larger angle to be subtended by the object at the eye and hence viewed in greater detail.

B. the formation of a virtual erect image.

C. increase in the field of view.

D. infinite magnification at the near point.

Answer :

Suppose the object has height h. Let it be viewed unaided at a distance, D.

The angle suspended at the eye is given by:

As the angle is small, the tangent of angle is approximately equal to the angle itself,

Now, let us view the object using the magnifying glass (convex lens). As the image is formed on the same side as the object, the image is virtual. Let the image distance be D.

The angle subtended by the image at the eye is given by:

Virtual image formed by a convex mirror is always enlarged. So,


Thus, option (a) is correct.

Option (b):

When we view an object through a magnifying glass, we see it on the same side as the object. The image formed is virtual, erect and enlarged as can be seen in the ray diagram above.

Option (c):

As the image forms is enlarged, the field view is reduced. Hence, option (c) is incorrect.

Option (d):

The magnification (both linear and angular) is given by:

Also, by similar triangles, we have

Note that v is the distance of the near point from the eye. As this distance is finite, m is finite (Practically, object distance (u) cannot be zero).

Thus, option (d) is incorrect.

Rate this question :

How useful is this solution?
We strive to provide quality solutions. Please rate us to serve you better.
Related Videos
Concave & Convex lensFREE Class
Young's Double Slit ExperimentFREE Class
Revision Quiz of 12th | Nuclear Physics71 mins
Bohr's Atomic Model46 mins
Nuclear Physics54 mins
Photoelectric Effect | World of Photons45 mins
Human Evolution | An Important ConceptFREE Class
Human Evolution38 mins
Rapid Quiz challenge - Cell Structure & Cell Division52 mins
Different high order thinking questions based on DNA structure39 mins
Try our Mini CourseMaster Important Topics in 7 DaysLearn from IITians, NITians, Doctors & Academic Experts
Dedicated counsellor for each student
24X7 Doubt Resolution
Daily Report Card
Detailed Performance Evaluation
view all courses