Question

30. Which statement is not correct for a convex mirror? a. The image distance is always positive. B. The object distance is with negative sign. b. Always forms an image behind the mirror. D. The focal length is always negative.
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Answer 1

Answer:

(D) The focal length is always negative(-ve)

Explanation:

By following sign convention, We know that the focal length of the convex mirror is always positive not negative as the focal length(of a convex mirror) lies on the right side or the positive side of x-axis.

Answer 2

D) The focal length is always negative. This statement is not correct for a convex mirror.

Explanation:

• A convex mirror is a mirror in which the reflective surface bulges toward the light source.
• The surface of a curved mirror can be convex, which means bulging outward.
• A convex mirror reflects the light outwards and is therefore not used to focus light.
• For a convex lens, the focal length is positive and is the distance at which a beam of collimated light will be focused to a single spot.
• A positive focal length indicates a focal length that the system converges to light.