Why does a driver prefer to use a convex mirror as a rear-view mirror in a vehicle?

Draw ray diagrams showing the image formation by a concave lens when an object is placed:Between focus and twice the focal length of the lens.

With the help of a diagram, show how when light falls obliquely on the side of a rectangular glass slab the emergent ray is parallel to the incident ray.

The image formed by a concave mirror is observed to be virtual, erect and larger than the object. Where should the position of the object be relative to the mirror? Draw ray diagram to justify your answer.

How is the reflection of light ray from a plane mirror different from the refraction of light ray as it enters a block of glass?

What is meant by power of a lens? What does its sign (+ve or -ve) indicate? State its S.I. unit. How is this unit related to focal length of a lens?

A concave mirror produces three times magnified real image of an object placed at 10 cm in front of it. Where is the image located?

A student places a candle flame at a distance of about 60 cm from a convex lens of focal length 10 cm and focuses the image of the flame on a screen. After that he gradually moves the flame towards the lens and each time focuses the image on the screen.

1. In which direction-toward or away from the lens, does he move the screen to focus the image?
2. How does the size of the image change?
3. How does the intensity of the image change as the flame moves towards the lens?
4. Approximately for what distance between the flame and the lens, the image formed on the screen is inverted and of the same size?

If a ray of light is incident on a plane mirror such that it makes an angle of 30with the mirror, then will be the angle of reflection?