The letter F is placed in front of a plane mirror:

1. How would its image look like when seen in a plane mirror?
2. What is the name of the phenomenon involved?

Identify the device used as a spherical mirror or lens in following cases, when the image formed is virtual and erect in each case.Object is placed between infinity and device, image formed is diminished and between pole and focus, behind it.

To find-the image-distance for varying object-distances in case of a convex lens, a student obtains on a screen a sharp image of a bright object placed very far from the lens. After that he gradually moves the object towards the lens and each time focuses its image of the screen.

1. In which direction - towards or away from the lens, does he move the screen to focus the object?
2. What happens to the size of the image - does it increase or decrease?
3. What happen when he moves the object very close to the lens?

Briefly describe how you would find the focal length of a concave mirror quickly but approximately.

Draw ray diagrams showing the image formation by a concave lens when an object is placed:
At the focus of the lens.

A convex lens of power 5D and a concave lens of power 7.5D are placed in contact with each other. What is the:

1. Power of this combination of lenses?
2. Focal length of this combination of lenses?

Draw a ray diagram to show the path of the reflected ray corresponding to an incident ray which is directed towards the principal focus of a convex. mirror. Mark on it the angle of incidence and the angle of reflection.

State three characteristics of the image formed by a convex mirror.

What is the difference between a real image and a virtual image? Give one example of each type of image.

Draw ray diagrams showing the image formation by a convex mirror when an object is placed:
At infinity.