# Difference between Diffraction and Interference

When looking at light interference and diffraction, it’s important to first understand the difference between the two. Interference is when two waves combine to form a new wave, while diffraction is the bending of light around an object. Visible light is made up of many different colors, which all travel at different speeds. This is what causes the bands of color you see in a rainbow. White light is made up of all the colors of visible light, while black light contains ultraviolet radiation that we can’t see. When white light shines on a diffraction grating, like those found in some sunglasses, it separates into its component colors.

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## What is Diffraction?

Diffraction is an important phenomenon that occurs when waves interact with obstacles in their path. When a wave encounters an obstacle, it is bent around the obstacle and continues on its way.

• Diffraction occurs with all types of waves, including sound waves, water waves, and light waves. Diffraction explains why we can hear someone speaking around a corner, why the edge of a shadow is blurry, and why ripples appear in water when an object is dropped into it.
• Diffraction also plays a role in optical illusions such as the elephant’s trunk illusion. Diffraction occurs because the wavefronts of a wave are bent when they encounter an obstacle.
• The amount of bending depends on the size of the obstacle relative to the wavelength of the wave. The larger the obstacle, the more pronounced the diffraction effect will be.

Diffraction is a natural phenomenon that cannot be avoided. However, it can be minimized by using smaller obstacles or by using waves with shorter wavelengths.

## What is Interference?

• Interference is the superposition of two or more waves that results in a new wave. The new wave has a different amplitude and/or phase from the original waves. Interference can be constructive or destructive. Constructive interference occurs when the amplitudes of the waves add together to create a wave with a higher amplitude.
• Destructive interference occurs when the amplitudes of the waves subtract from each other to create a wave with a lower amplitude. Interference is used in Young’s double slit experiment to determine the wave-like nature of light.
• Interference is also seen in acoustics and optics. Interference fringes are areas of constructive and destructive interference. Interference patterns are created when two sources of waves are overlapped.

## Difference between Diffraction and Interference

Diffraction and interference are both wave phenomena that arise from the wave nature of light. Diffraction occurs when waves encounter an obstacle or a slit and interfere when two waves meet.

• The key difference between diffraction and interference is that diffraction can occur with any type of wave, whereas interference can only occur with waves that have the same wavelength.
• Diffraction results in a spreading out of waves, while interference results in the reinforcement or cancellation of waves. Both diffraction and interference can be used to explain the patterns formed by light passing through a slit.
• In general, diffraction is a more common phenomenon than interference, since it does not require two identical wave sources. However, interference can produce more dramatic effects, such as the overlapping of two light sources to produce darkness.

## Conclusion

Interference and diffraction are two different phenomena that can occur when light waves interact with one another. When interference occurs, the crests and troughs of the waves line up and create an increase in amplitude. This creates a new wave that is larger than either of the original waves. Diffraction, on the other hand, occurs when a wave encounters an obstacle. The wave will bend around the obstacle and spread out into the surrounding space. Understanding these differences can help you apply them to specific situations for optimal results.