Two images Y and X are formed by a plane mirror and a convex mirror respectively. Which of the following is correct about their characteristics?

Analyze the question: Y is the image from a plane mirror and X is the image from a convex mirror. We need the statement that correctly compares their characteristics.

Concept:

• Plane mirror image: virtual, erect, same size as the object, laterally inverted (left and right swapped, but not upside down), and as far behind the mirror as the object is in front. Magnification m = 1.
• Convex (diverging) mirror image: always virtual, erect, and diminished, whatever the object distance. It forms between the pole and the focus behind the mirror. Magnification 0 < m < 1.

Checking each option:

• A. Both are inverted: False. Both images are erect.
• B. Magnification of Y is greater than one, X is one: False. For the plane mirror m = 1, and for the convex mirror m < 1.
• C. Magnification of Y is one while X is less than one: True. The plane mirror gives m = 1 and the convex mirror gives a diminished image, so m < 1.
• D. Y is inverted while X is erect: False. The plane mirror image is erect. It is only laterally inverted, which is not the same as being upside down.
• E. Y is real while X is virtual: False. Both images are virtual.

Tip: Remember this for mirrors:

• Plane mirror: virtual, erect, m = 1.
• Convex mirror: virtual, erect, diminished, m < 1, and it gives a wide field of view. That is why it is used as a car rear-view mirror and for security mirrors.

If an option says a convex mirror image is real or inverted, eliminate it immediately.