Which type of mirror is used in a solar furnace? Support your answer with reason.

Refractive index of diamond with respect to glass is 1.6 and absolute refractive index of glass is 1.5. Find out the absolute refractive index of diamond.

Your eye contains a convex lens. Why is it unwise to look at the sun?

List four precautions which a student should observe while determining the focal length of a given convex lens by obtaining image of a distant object on a screen.

Describe with the help of a diagram, the nature, size and position of the image formed when an object is placed beyond the centre of curvature of a concave mirror.

Draw a ray diagram to show the formation of a real magnified image by a convex lens. (In your sketch the position of object and image with respect to the principal focus of lens should be shown clearly).

What type of lens is shown in the diagram on the right? What will happen to the parallel rays of light? Show by completing the ray diagram.

An object is placed well outside the principal focus of a convex lens. Draw a ray diagram to show how.

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

Write down a formula for the magnification produced by a concave mirror.

1. In terms of height of object and height of image.
2. In terms of object distance and image distance.