Abhishek Chandra Solutions for Chapter: Light - Reflection and Refraction, Exercise 2: EXERCISE

In order to use a convex lens as a magnifying glass, where should the object be placed?

If we wish to obtain an image thrice as large as the object using a converging lens of focal length $20 \mathrm{cm}$, the object distance should be

Case I: Ryan first looks perpendicularly into a pond.

Case II: He looks into the pond obliquely.

Now, choose the correct option with regard to the apparent depth of the pond:

A thin converging lens forms a (i) real magnified image; (ii) virtual magnified image of an object placed in front of it.

(a) Write the positions of the objects in each case.

(b) If the lens is now cut into two halves along the principal axis, how will the focal length and the intensity of image formed by half lens be affected?

A convex lens was used to form images of an object kept at different positions. The object positions used were $120 \mathrm{cm}, 60 \mathrm{cm}, 40 \mathrm{cm}, 30 \mathrm{cm}$ and $25 \mathrm{cm}$. The image positions, not necessarily in correct order, were $40 \mathrm{cm}, 24 \mathrm{cm}, 100 \mathrm{cm}, 30 \mathrm{cm}$ and $60 \mathrm{cm}$. Write the correct order of the image distances.

A convex lens was used to form images of an object kept at different positions. The object positions used were $120 \mathrm{cm}, 60 \mathrm{cm}, 40 \mathrm{cm}, 30 \mathrm{cm}$ and $25 \mathrm{cm}$. The image positions, not necessarily in correct order, were $40 \mathrm{cm}, 24 \mathrm{cm}, 100 \mathrm{cm}, 30 \mathrm{cm}$ and $60 \mathrm{cm}$.

Find the focal length of the lens.

A convex lens was used to form images of an object kept at different positions. The object positions used were $120 \mathrm{cm}, 60 \mathrm{cm}, 40 \mathrm{cm}, 30 \mathrm{cm}$ and $25 \mathrm{cm}$. The image positions, not necessarily in correct order, were $40 \mathrm{cm}, 24 \mathrm{cm}, 100 \mathrm{cm}, 30 \mathrm{cm}$ and $60 \mathrm{cm}$.

Which position of the object among the given positions will give the largest image?

The filament of a lamp is $60 \mathrm{cm}$ away from a screen. A four times magnified image of the filament is formed on the screen by a lens. What is the nature of the lens? Calculate the distance of the filament from the lens. Also, calculate the focal length of the lens.