An object is 8cm high. It is desired to form a real image 4cm high at 20cm from the lens. The focal length and power of lends are

When an object is placed 40cm from a diverging lens, its virtual image is formed 20cm from the lens. The focal length and power of lens are

When an object is placed 40cm from a diverging lens, its virtual image is formed 20cm from the lens. The focal length and power of lens are

An object is kept at 60 cm in front of a convex lens. Its real image is formed at 20 cm from the lens . Find the focal length and power of the lens.

An object is kept at 20 cm in front of a convex lens and its real image is formed at 60 cm from the lens . Find The focal length and power of the lens .

An object of height 2 cm is kept at 30 cm from a convex lens . Its real image is formed at 60 cm from the lens .Find the focal length and power of the lens.

An object of height 2 cm is kept at 30 cm from a convex lens . Its real image is formed at 60 cm from the lens. Find the focal length of power of the lens.

An object is kept at 20 cm in front of a convex lens and its real image is formed at 60 cm from the lens. Find (1) the focal length of the lens (2) the image if the height of the object is 6 cm.

An object is kept at 20 cm in front of a convex lens its real image is formed at 60 cm from the lens. Find (i) the focal length of the lens (ii) the height of the image if the height of the object is 6 cm.

An object 4 cm high is placed at a distance of 10 cm from a convex lens of focal length 20 cm. Find the position, nature and size of the image.

A lens forms a real image 3 cm high of an object 1 cm high. If the separation of object and image is 15 cm, find the focal length of the lens.