A doctor prescribes a rectifier lens of power +1.5 D. Find the focal length of the lens. Is the lens converging or diverging?

An object of size 7.0 cm is placed at a distance of 27 cm in front of a concave mirror of focal length 18 cm. At what distance from the mirror should a screen be placed so that a clear focused image of the object is formed? Find the size and nature of an object.

An object of length 0.5 cm is placed at a distance of 20 cm in front of a convex mirror of radius of curvature 30 cm. Find the position, nature and size of the image.

The magnification of an image formed by plane mirror is +1. What does this mean?

An object is placed at a distance of 10 cm from a convex mirror of focal length 15 cm. Find the position and image of the image.

An object is placed at a distance of 15 cm from a convex lens of focal length 10 cm. Write the nature and magnification of the image.