Final answer:
Light can be modeled both as rays for image formation with mirrors and lenses, and as waves for phenomena like diffraction and interference, using methods such as laser demonstrations with aluminum foil and a razor blade.
Step-by-step explanation:
To model how light travels in a wave, one can use several different methods depending on whether we are considering its ray or wave characteristics. Light can be modeled as a ray when the devices it interacts with are large compared to its wavelength. Ray tracing is especially useful when working with mirrors and lenses, as it simplifies the calculations of image formation.
However, for phenomena such as diffraction and interference, which occur when the size of the structures involved is comparable to the wavelength of light, modeling light as a wave is essential. A classic demonstration to support the wave model of light could involve the use of a laser, a piece of aluminum foil, and a razor blade to observe interference patterns. This setup demonstrates how light waves can constructively and destructively interfere with each other, forming a pattern of bright and dark fringes, supporting the concept that light has wavelike properties.
Additionally, Huygens's principle can be invoked to explain why waves, including light, bend around corners and spread out after passing through slits. Therefore, depending on the physical situation, light can be effectively modeled either as rays or as waves, supporting the concept that different models of light are appropriate at different scales.