Geometric raindrop

A raindrop is often represented as a geometrically perfect sphere, an idealized form that rarely exists in reality. This simplification helps in understanding the physics of rainbows, even though actual raindrops seldom maintain a perfectly spherical shape.

  • Although the idealized geometry of raindrops aids in understanding rainbows, real raindrops vary in shape due to factors such as size, speed of descent, and turbulence. Each rainbow we observe is unique, shaped by chance and a range of environmental conditions.
  • In summary, the form of a rainbow and the arrangement of raindrops within it depend on various changing factors, including the size, shape, and distribution of the droplets, the position of the sun, the observer’s location, atmospheric clarity and composition, and the presence of additional light sources or reflective surfaces. Every rainbow is a one-of-a-kind phenomenon, shaped by both random variations and the surrounding environment.
About light rays
  • The idea of light rays is a way to simplify how we think about the behaviour of light. In the case of rainbows, it affects how we think of light as it approaches, passes through and exits raindrops towards an observer.
    • In reality, the notion of light rays does not describe an inherent physical property of light; rather, it’s a simplification for illustrative purposes.
    • More precise descriptions of light refer to it as composed of particles called photons, or as exhibiting wave-like properties.
Related diagrams

Each diagram below can be viewed on its own page with a full explanation.

References
  • A raindrop is often represented as a geometrically perfect sphere. This is an idealized form that rarely exists in the real world. The simplification aids in comprehending the physics of rainbows, even though real-life raindrops seldom maintain such perfect spherical forms.
  • The understanding derived from studying the idealized geometry of raindrops can be applied to every rainbow even though:
    • The shape of a real raindrop is highly variable and depends on factors including size, speed of descent, and turbulence.
    • Each rainbow observed in our daily life and the arrangement of droplets within it is unique due both to chance and to a wide range of environmental factors.
    • By way of summary, the form of a rainbow and the arrangement of raindrops within it depends on a variety of unique and changing conditions. These include the size, shape, and arrangement of the raindrops that make up the rainbow, as well as the position of the sun, the observer’s location, the clarity and composition of the atmosphere, and the presence of any other light sources or reflective surfaces. So, each rainbow that we observe is unique, shaped by both random variations and a wide array of environmental factors.