What is the definition of optics?

Optics is defined as the branch of physics devoted to the study of light and its interaction with matter. This field encompasses various phenomena related to light, including reflection, refraction, diffraction, and dispersion. It examines how light behaves as it travels through different media and how it interacts with materials, leading to the formation of images and various optical devices such as lenses and mirrors.

The correct answer captures the essence of optics by highlighting its focus on light, which is crucial for understanding how everything from everyday vision to advanced technologies like lasers and fiber optics works. Understanding optics is fundamental in diverse applications, including medical imaging, photography, and astronomy, where the characteristics of light play a vital role.

Other choices reference different scientific disciplines: the study of sound relates to acoustics, the science of temperature pertains to thermodynamics, and the analysis of motion refers to mechanics. Each of these fields serves its unique purpose but does not encompass the study of light and its interactions, which is the core of optics.