WEEK 4
LC10/ LC 11
Dispersion, scattering, interference, and diffraction are all phenomena related to the behavior of waves,
including electromagnetic waves like light or sound waves. While they may seem similar, they describe
distinct processes:
Dispersion:
1. Dispersion refers to the separation of different wavelengths of a wave as it passes through a
medium.
This separation occurs because the velocity of a wave depends on its wavelength in certain mediums.
Common examples of dispersion include the splitting of white light into its component colors when
passing through a prism, or the separation of colors in a rainbow caused by the dispersion of sunlight in
raindrops.
Scattering:
2. Scattering occurs when waves encounter obstacles or irregularities in a medium and are
redirected in various directions.
Scattering can occur with any type of wave, including light, sound, or electromagnetic waves.
The scattering process can be responsible for various phenomena, such as the blue color of the sky
(Rayleigh scattering of sunlight in the atmosphere), or the diffusion of sound waves in a room due to
interactions with surfaces.
Interference:
3. Interference is the phenomenon that occurs when two or more waves interact with each other.
It can result in either reinforcement (constructive interference) or cancellation (destructive interference)
of the waves.
Interference patterns can be observed in various contexts, such as the alternating bright and dark bands
in a double-slit experiment with light or the patterns formed by overlapping ripples in water.
Diffraction:
4. Diffraction is the bending or spreading of waves around obstacles or through openings.
It occurs when waves encounter an obstruction that is comparable in size to their wavelength.
Diffraction can cause waves to bend around corners or spread out after passing through a narrow slit,
leading to characteristic patterns of intensity distribution.
For example, the diffraction of light through a narrow slit results in a pattern of alternating bright and
dark fringes known as a diffraction pattern.
