WAEC 2014 Physics · Question 39

The functional difference between a lens and a mirror is that a lens

Options

A.reflects a beam of light while a mirror refracts it
B.refracts a beam of light while a mirror reflects it
C.absorbs incident rays while a mirror transmit them
D.transmits incidents ray whle a mirror absorbs them

Answer: B. refracts a beam of light while a mirror reflects it

Explanation written with AI and checked against the answer key

Step 1: Analyze the question The question asks how a lens differs from a mirror in the way each handles light.

Step 2: Explain the concept

A lens is a piece of transparent glass or plastic. Light passes through it and bends. This bending is called refraction.
A mirror has a polished, shiny surface. Light bounces off it. This bouncing is called reflection.

So the main functional difference is how each one changes the path of light: a lens refracts it and a mirror reflects it.

Step 3: Check each option

A. Wrong. It swaps the two roles. A lens does not reflect and a mirror does not refract.
B. Correct. A lens refracts light, and a mirror reflects it.
C. Wrong. A lens does not absorb the light, and a mirror does not transmit it.
D. Wrong. A lens does transmit light, but a mirror is meant to reflect light, not absorb it.

Step 4: Answer The correct option is B.

Tip: Remember "Lens = Light goes Layer-through (refraction); Mirror = Make it bounce back (reflection)." Also, converging lenses and diverging lenses use refraction, while concave and convex mirrors use reflection. WASSCE often tests this contrast.

AI can make mistakes. Report anything that looks wrong.