Two concave lenses, eacb of focal length 30 cm are placed in contact with each other. Find the power of the combination.
Ten identical converging thin lenses,each of focal length 10cm are in contact .What is the power of the combined lens.
A concave lens of focal length 20 cm placed in contact with a plane mirror acts as a
A convex lens of focal length x and a concave lens of focal length y are placed in contact. The focal length of the combination is
A convex lens of focal length A and a concave lens of focal length B are placed in contact. The focal length of the combination is
Two convex lenses of focal length 10 cm each are combined. What will be the focal length of the combined lens ?
Two thin concave lenses of focal lengths 10 cm and 30 cm and a thin convex lens of focal length 30 cm are kept in contact. What will be the power of lens combination ?
A convex lens of focal length 40 cm a concave lens of focal length 40 and a concave lens of focal length 15 cm are placed in contact. The power of this combination of are placed in contact. The power of this combination in diopters is
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.