The algebraic summation of waves leading to patterns of minima and maxima is called:

• A. Interference
• B. Scattering
• C. Absorption
• D. Refraction

Answer: (A)

Interference is the phenomenon that occurs when two or more waves overlap and their displacements add together. Because the waves may be in or out of phase, their amplitudes combine algebraically: in-phase contributions reinforce each other to produce maxima, while out-of-phase contributions partially or completely cancel to produce minima. This superposition of wave amplitudes creates the alternating pattern of bright (maxima) and dark (minima) fringes seen in many wave experiments.

Other terms describe different wave interactions: scattering is the redirection of waves by objects, absorption is energy removal by the medium, and refraction is the change in direction due to a speed change between media. These do not inherently produce the alternating maxima and minima patterns from simple algebraic summation of waves.