What is the relation between the focal length and radius of curvature of a spherical mirror (concave mirror or convex mirror)? Calculate the focal length of a spherical mirror whose radius of curvature is 25cm.

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.

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

Show the lateral displacement of the ray on the diagram.

Explain with the help of a diagram, why the convex lens is also called a converging lens.

A student focuses the image of a well illuminated distant object on a screen using a convex lens. After that he gradually moves the object towards the lens and each time focuses its image on the screen by adjusting the lens.

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

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

An object is placed at a distance of 40cm in front of a convex mirror of radius of curvature 40cm. List four characteristics of the image formed by the mirror.

Describe the nature of image formed when the object is placed at a distance of 20cm from a concave mirror of focal length 10cm.