* Light's Interaction with Matter: Light is an electromagnetic wave. When it enters a medium, it interacts with the atoms and molecules of that medium. This interaction causes the light to slow down.
* Refractive Index: The extent to which light slows down in a medium is measured by its refractive index. The higher the refractive index, the more the light slows down. For example, water has a higher refractive index than air, so light travels slower in water.
* Important Note: The frequency of light (its color) remains constant when it enters a different medium. However, the wavelength of light changes to accommodate the change in speed. This change in wavelength is what causes refraction, the bending of light as it passes from one medium to another.
Here's a simple analogy: Imagine light as a car traveling on a road. When the car enters a denser area (like a forest), it slows down. Similarly, light slows down when it enters a denser medium.
Key Points:
* Light travels at its fastest speed in a vacuum (approximately 299,792,458 meters per second).
* Light slows down when it enters a medium like air, water, glass, etc.
* The amount of slowing down depends on the refractive index of the medium.
* The frequency of light remains constant, but the wavelength changes.
Let me know if you'd like more details or examples!
