Sample interview questions: Can you explain the concept of light propagation and its behavior in different media?
Sample answer:
- Light Propagation in Vacuum:
- In a vacuum, light travels in a straight line at a constant speed, approximately 299,792,458 meters per second, known as the speed of light.
- The direction of propagation is determined by the wave vector, which is perpendicular to the wavefronts.
-
The speed of light in vacuum is a fundamental constant and is one of the cornerstones of modern physics.
-
Refraction of Light:
- When light passes from one medium to another, it undergoes a change in direction, known as refraction.
- The angle of refraction is determined by the refractive indices of the two media and the incident angle of the light.
- The refractive index is a dimensionless quantity that describes how much light is bent when it passes from one medium to another.
-
The higher the refractive index, the more the light is bent.
-
Reflection of Light:
- When light encounters a surface, it can be reflected, meaning it bounces off the surface and changes direction.
- The angle of reflection is equal to the angle of incidence, and both are measured with respect to the normal (perpendicular) to the surface.
-
Reflection is governed by the laws of reflection, which state that the incident ray, the reflected ray, and the normal to the surface at the point of incidence all lie in the same plane.
-
Absorption of Light:
- When light interacts with matter, some of its energy can be absorbed by the material.
- The amount of light absorbed depends on the wavelength of the light and the properties of the material.
-
Absorption of light can lead to various phenomena, such as heating, chemical reactions, and fluorescence.
-
Scattering of Light:
- Scattering is the process by which light is redirected in various directions due to interactions with particles or molecules in a medium.
- There are two main types of scattering: Rayleigh scattering and Mie scattering.
- Rayleigh scattering occurs when the particles are … Read full answer