Profile
Settings
Refer your friends
Sign out
When you see light shining through a thin slit in a dark room, it often looks like there are several beams of light coming from the slit. This is because light passing through the slit is diffracted into several different colours. But what is diffraction, and how does it differ from interference? In this article, we will discuss the differences between diffraction and interference, and provide examples of each phenomenon.
What Is Diffraction?
Diffraction is the bending of waves around an obstacle. When light waves diffract, they bend around objects in their path. This is why you can see light shining through a narrow slit in a dark room. The light waves bend around the edges of the slit, and this causes the light to disperse into several different colours.
What Is Interference?
Interference is the superposition of two or more waves. When two waves interfere with each other, they create a new wave. This new wave is the sum of the amplitudes of the two original waves. Interference can be of two types: constructive or destructive. If we look at the explanation, constructive interference takes place when the two waves have the same amplitude, and destructive interference happens when the two waves have opposite amplitudes.
Examples of Diffraction and Interference
One of the most famous examples of diffraction is the Rainbow. Rainbows are created when sunlight diffracts through water droplets. The light waves bend around the edges of the water droplets, and this causes the light to disperse into different colours.
Another example of diffraction is a CD or DVD. CDs and DVDs are coated with a thin layer of metal. When light shines on a CD or DVD, the light waves diffract off the surface of the disc. This is what causes the reflections that you see on a CD or DVD.
An example of interference is Young’s Double Slit Experiment. In this experiment, two slits are cut into a screen. The light shines through both slits, and the light waves interfere with each other. This creates a pattern of light and dark bands on the screen.
Difference Between Diffraction And Interference
- Meaning: The difference between diffraction and interference is that diffraction is the bending of waves around an obstacle while interference is the superposition of two or more waves.
- When it occurs: Diffraction occurs when light waves bend around objects in their path. Interference occurs when two waves interact with each other.
- Effect: The effect of diffraction is that it disperses light into different colours. The effect of interference is that it creates a new wave.
- Examples: An example of diffraction is the Rainbow. An example of interference is Young’s Double Slit Experiment.
When rainbows form, sunlight diffracts through water droplets and the light waves bend around the edges of the water droplets. This causes the light to disperse into different colours. In Young’s Double Slit Experiment, two slits are cut into a screen and the light shines through both slits. The light waves interfere with each other and this creates a pattern of light and dark bands on the screen.
Conclusion
In short, interference is the result of two waves overlapping each other, while diffraction occurs when a wave encounters an obstacle. The difference between interference and diffraction can be seen in how they affect light. When light passes through two closely spaced slits, it forms an interference pattern on a screen behind the slits. This is because the light waves overlap as they pass through the slits and create bright and dark bands on the screen. However, if you put a barrier like a piece of paper in front of one slit, the light passing through that slit will not cause any interference because it won’t have anything to overlap with. Instead, you’ll see a single band on the screen caused by the light from the other slit diffracting around the edge of the paper.
