A lens form a diminshed and erect image of an object. The magnifiation is `(1)/(4)`. Find ratio of distances between object and focus and focus and image:

A mirror produces magnified erect image of an object. The nature of the mirror is

An object is placed 12cm in front of a lens to form an image on a screen. The size of the image is twice that of the object. What is the distance between the object and the image?

A convex lens forms an image of an object on a screen ,The height of the image is 9cm The lens is now disiplaced between the object on the screen.the height of this image is 4cm .the distance between the object and the screen is 90cm

A cocave lens forms the image of an object such that the distance between the object and image is 10 cm and the magnification produced is 1/4. the focal length of the lens will be

A concave lens forms the image of an object such that the distance between the object and image is 10 cm and the magnification produced is 1//4 . The focal length of the lens will be