Lens

What is differences between lens and mirror?

An object is placed at the following distances from a convex lens of focal length $10 \mathrm{cm}$.
(a) $8 \mathrm{cm}$

(b)$15 \mathrm{cm}$

(c) $20 \mathrm{cm}$

(d) $25 \mathrm{cm}$
Which position of the object will produce
    i. A diminished, real and inverted image?
    ii. A magnified, real and inverted image?
    iii. A magnified, virtual and erect image?
    iv. An image of the same size as object?
Justify your answer in each case.

In a convex lens, when the object is placed at infinity the size of the image formed is _____.

If an object is placed at the focus of a convex lens, its image is

A real inverted image of size of object is to be formed by holding the object at $1 \mathrm{m}$ from a convex lens. What should be the focal length of the lens.

An object of height $20 \mathrm{cm}$ is kept in front of a convex lens and its distance from lens is $80 \mathrm{cm}$. If the focal length is $30 \mathrm{cm}$, calculate the distance of image, its nature, size and magnification.

Complete the ray diagram.

Why is an image through a convex lens used in spectacles does not seems inverted?

The convex lens always gives small virtual image.

With the help of diagram explain the centre of curvature.

Which lens is known as diverging lens?

A ray of light is incident on a lens parallel to its principal axis. After refraction, the ray passes through or appear to come from:

a converging lens

The convex lens is known as _____ lens.

The classification of a lens depends on how the light rays bend when they pass through the lens.

What are the types of lenses?

If $F$ be the focal length of a convex lens, then the nature of image of an object placed at a distance $2F$ will be :

The central point of a lens is known as:

What is a Convex lens? Discuss the image formation by a convex lens for different positions of an object.

The $I_1,I_2 and I_3$ rays coming to the system formed by divergent X and convergent Y lenses whose principal axes are coincident and focal lengths are as shown in the figure.

Accordingly, which of the $I_1, I_2 and I_3$ rays have been given the correct path after the second time in the lens?
(Distances between points are equal and about.)