0
You visited us 0 times! Enjoying our articles? Unlock Full Access!
Question

A card sheet divided into squares each of size 1mm2 is being viewed at a distance of 9cm through a magnifying glass (a converging lens of focal length 9cm) held close to the eye.
In order to view the squares distinctly with the maximum possible magnifying power.
(a) What is the magnification produced by the lens? How much is the area of each square in the virtual image?
(b) What is the angular magnification (magnifying power) of the lens?
(c) Is the magnification in (a) equal to the magnifying power in (b)?
Explain:

Solution
Verified by Toppr

(a) Area of each square , A=1mm2
Object distance u=9cm
Focal length of the converging lens , f=10cm
For image distance v, the lens formula can be written as
1f=1v1u
By putting the values we get v=90cm
Now magnification,
m=uv=609=10
Area of each square in the virtual image = 102A=102×1=100mm2

(b) Magnifying power of the lens
d|u|=259=2.8

(c) The magnification in (a) is not same as the magnifying power in (b).
The ,magnification magnitude is
(|vu|) and the magnifying power is (d|u|)
The two quantities will be equal when the image is formed at the near point (25cm).

Was this answer helpful?
0
Similar Questions
Q1
A card sheet divided into squares each of size 1mm2 is being viewed at a distance of 9cm through a magnifying glass (a converging lens of focal length 9cm) held close to the eye.
In order to view the squares distinctly with the maximum possible magnifying power.
(a) What is the magnification produced by the lens? How much is the area of each square in the virtual image?
(b) What is the angular magnification (magnifying power) of the lens?
(c) Is the magnification in (a) equal to the magnifying power in (b)?
Explain:
View Solution
Q2

A card sheet divided into squares each of size 1 mm2 is being viewed at a distance of 9 cm through a magnifying glass (a converging lens of focal length 9 cm) held close to the eye.

(a) What is the magnification produced by the lens? How much is the area of each square in the virtual image?

(b) What is the angular magnification (magnifying power) of the lens?

(c) Is the magnification in (a) equal to the magnifying power in (b)?

Explain.

View Solution
Q3
A card sheet divided into squares each of size 1mm2 is being viewed at a distance of 9cm through a magnifying glass (a converging lens of focal length 9cm) held close to the eye and the magnifying glass if the virtual image of each square is to have an area of 6.25mm2. Would you be able to see the squares distinctly with your eyes very close to the magnifier?
View Solution
Q4
(a) At what distance should the lens be held from the figure in Exercise 9.29 in order to view the squares distinctly with the maximum possible magnifying power? (b) What is the magnification in this case? (c) Is the magnification equal to the magnifying power in this case? Explain.
View Solution
Q5
A wire mesh consisting of very small squares is viewed at a distance of 8 cm through a magnifying converging lens of focal length 10 cm, kept close to the eye. The magnification produced by the lens is.
View Solution