In Fig,, if the image of object O has to coincide with itself, then where must the object be placed at a distance from the lens?

A lens with a focal length of 25 cm produces real image of an object at a distance of 50 cm from the lens. At what distance the object placed from the lens?

When an object is placed at a distance of 36 cm from a convex lens, an image of the same size as the object is formed. What will be the nature of image formed when the object is formed. What will be the nature of image formed when the object is placed at a distance of: a) 10 cm from the lens? b) 20 cm from the lens?

An extended real object is placed perpendicular to the principle axis of a concave of focal length 10 cm , such that the images found is half the size of object (a) Find the object distance from the lines (b) Find the image distance from the lens

An object is placed in front of a thin convex lens of focal length 30cm and a plane mirror is placed 15cm behind the lens.If the final image of the object coincides with the object the distance of the object from the lens is

A convex lens produces a real image double the size of the object, when the object is placed at a distance 18 cm from it. Where should the object be placed to produce a real image three times the size of the object?

A thin convex lens of focal length 30 cm is placed in front of a plane mirror. An object is placed at a distance x from the lens (not in between lens and mirror ) so that its final image coincides with itself. Then, the value of x is

A thin convex lens of focal length 30 cm is placed in front of a plane mirror. An object is placed at a distance x from the lens (not in between lens and mirror ) so that its final image coincides with itself. Then, the value of x is