What are real-life examples of diffraction?

Real-life examples of diffraction include rainbow formation, sound wave spreading, and the pattern created by a CD or DVD.

Diffraction is a wave phenomenon that occurs when a wave encounters an obstacle or a slit. It is the bending of waves around the corners of an obstacle or aperture into the region of the geometrical shadow of the obstacle. In our daily life, we can observe several examples of diffraction.

Rainbows are a beautiful natural example of diffraction. When sunlight passes through raindrops, it is diffracted, or spread out, into its various colours. This is because different colours of light have different wavelengths, and they are bent by different amounts by the water droplets. The result is a spectrum of colours in the shape of a semi-circle.

Sound waves also exhibit diffraction. When someone speaks, the sound waves spread out in all directions, not just in a straight line. This is why you can hear someone speaking even if they are not directly in front of you. The sound waves are diffracted around obstacles, such as walls or furniture, allowing the sound to reach your ears.

Another common example of diffraction can be seen in the pattern created by a CD or DVD. When light shines on a CD or DVD, it is diffracted by the tiny grooves in the disc. This causes the light to spread out and create a rainbow-like pattern. This is similar to how a diffraction grating works in a laboratory, where a series of small slits causes light to spread out and form a spectrum.

IGCSE Physics Tutor Summary: In summary, diffraction is the spreading of waves, like light and sound, when they meet obstacles. Examples include the rainbow's colours, created when sunlight diffracts through raindrops; the way sound travels around barriers, letting us hear things not directly in front of us; and the rainbow patterns on CDs or DVDs, caused by light diffracting off their grooves.