A convex lens of focal length `30 cm` and a concave lens of focal length `60 cm` are placed in combination. If an object is placed `40 cm` away from the combination, find the position of the image.

A convex lens of foal length 30 cm and a concave lens of focal length 60 cm are placed in contact.If the object is placed 40 cm away from the combination ,, find the position of the image.

A convex lens of focal length 80 cm and a concave lens of focal length 50cm are placed in contact. The resulting will be—

A convex lens of focal lenth 30 cm and a concave lens of focal length 60 cm are placed in contact.Find the power of the combination.

A convex lens of focal length 30 cm and a concave lens of focal length 0.6m are placed in contact. Find the power of the combination.

A convex lens of 40 cm focal length is combined with a concave lens of focal length 25 cm. The power of combination is

A convex lens of focal length 10 cm is placed coaxially 5 cm away from a concave lens of focal length 10 cm. If an object is placed 30 cm in front of the convex lens, find the position of the final image formed by the combined system.

A convex lens of focal length 40 cm is in contact with a concave lens of focal length 25 cm. The power of the combination is