Sound and Electromagnetic Waves

Properties of Sound Waves

Sound waves are a type of mechanical wave, which require a medium (i.e., solid, liquid, or gas) to propagate.
They are longitudinal waves, which means they move the medium particles in the direction parallel to the energy transport.
Sound waves are characterised by their frequency, amplitude, and speed. Frequency of sound corresponds to pitch while the amplitude relates to loudness.
The speed of sound is dependent on the temperature, humidity, and pressure of the medium through which it is travelling.
Echoes and reverberations are phenomena associated with sound based on the concept of reflection of waves.
Sound cannot travel through a vacuum because there are no particles in a vacuum to compress or vibrate.

Electromagnetic waves are made up of oscillating electric and magnetic fields and can travel through the vacuum of space.
All electromagnetic waves travel at the same speed, the speed of light (c), which is approximately 300,000 kilometres per second.
The frequency and wavelength of an electromagnetic wave are inversely proportional. Increasing the frequency leads to a decrease in wavelength and vice versa.
The electromagnetic spectrum is the range of all electromagnetic waves, ordered by decreasing wavelength and increasing frequency.
Types of electromagnetic waves include (from long wavelength/low frequency to short wavelength/high frequency): radio waves, microwaves, infrared, visible light, ultraviolet, X-rays, and gamma rays.
Each type of electromagnetic wave has a unique range of frequencies, wavelengths, and energy levels.

Both sound and electromagnetic waves can reflect, refract, and diffract when they interact with matter.
Reflection involves the wave bouncing off an obstacle. In sound waves, this leads to phenomena such as echoes.
Refraction occurs when a wave changes direction upon entering a different medium due to a change in speed. This can be observed in both light waves (forming rainbows) and sound waves (changing perceived loudness).
Diffraction is the bending of waves around obstacles and can occur with both sound and light waves. The amount of diffraction depends on the size of the obstacle compared with the wavelength of the wave.