A thin convergent lens produces the images of a certain object on a screen. The height of image is 4cm. Without changing the distance between the object and the screen, the lens is shifted, and it is found that the height of the second sharp image is 9m. Determine the height of the object (in cm)

The distance between the object and its real image from the convex lens is 60 cm and the height of image is two times the height of object . The focal length of the lens 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 lens produces a virtual image between the object and the lens. Name the lens.

A convex lens forms an image of an object on a screen. The height of the image is 9 cm . The lens is now displaced until an image is again obtained on the screen. Then height of this image is 4 cm . The distance between the object and the screen is 90 cm.

A convex lens produces an image of a condle flame upon a screen whose distance from candle is D. When the lens is displaced through a distance x , (the distance between the candle and the screen is kept constant), it is found that a sharp image is again produced upon the screen. Find the focal length of the lens in terms of D and x .

A lens with a focal length of 16 cm produces a sharp image of an object in two positions, which are 60 cm apart. Find the distance from the object to the screen.

In a displacement method the distance between the object and the screen is 70 cm and the focal length of the lens is 16 cm, find the separations of the magnified and diminished image position of the lens.

A convex lens is used to obtain a magnified image of an object on a screen . The object is at a distance 10 m from the lens . If the magnification is 19. the focal length of the lens is

An object 25 cm high is placed in front of a convex lens of focal length 30 cm . If the height of image formed is 50 cm , find the distance between the object and the image (real and virtual)?

A convex lens forms a real image of an object for its two different positions on a screen. If height of the image in both the cases be 8 cm and 2 cm , then height of the object is