Suppose the lower half of the concave mirror's reflecting surface is covered with an opaque material.What effect this will have on the image of the object?Explain.

Suppose that one half of the reflecting surface of a concave mirror is covered with black soot.How will the image of an object placed in front of the mirror be affected?

One half of a convex lens is covered with a black paper .Will this lens produce a complete image of the object? Explain your observation

When the image formed by a concave mirror is at infinity then what is the position of the object?

The image formed by a concave mirror is observed to be virtual, erect and larger than object,where should be the position of the object?

If a concave mirror of focal length f produces a real image n times the size of the object,then find the distance of the object from the mirror.

A short linear object of length b lies along the axis of a concave mirror of focal length f at a distance u from the pole. What is the size of the image?

Find the position of an object,which when placed in front of a concave mirror of focal length 20 cm,produces a virtual image,which is twice the size of the object.

The image of a candle is formed by a convex lens on a screen. The lower half of the lens is painted black to make it completely opaque. Draw the ray diargram to show the image formation. How will this image be different from the one obtained when the lens is not painted black?