Question

The inner surface of a spoon acts like a _______ mirror, while the outer surface of a spoon acts like a _______ mirror.
1. Flat; Convex
2. Convex; Concave
3. Bi-nuclear (bifocal); Flat
4. Concave; Convex

Answer 1

Correct Answer - Option 4 : Concave; Convex

The correct answer is Concave; Convex.

• The curved shining surface of a polished steel spoon acts as a mirror.  
• The most common example of a curved mirror is a spherical mirror.
• If the reflecting surface of a spherical mirror is concave (hollowed or rounded inward like the inside of a bowl), it is called a concave mirror & if the reflecting surface is convex (curved or rounded outward like the exterior of a sphere or circle), then it is a convex mirror.
• Thus, the inner surface of a polished steel spoon acts like a concave mirror, while its outer surface acts as a convex mirror.
• A concave lens has at least one concave surface and it diverges the light rays refracted through it.   
• A mirror with a flat or plane reflective surface is called a plane mirror and has several uses like in solar cookers, dentistry tools, dressing table mirrors, periscopes, security, etc.