In theory, electromagnetic waves cover a wide range of frequencies, from less than 1 Hz (e.g., radio waves) to over 10²⁴ Hz (gamma rays). However, practical considerations, such as technological limitations and safety concerns, determine the detectable frequency ranges. Humans typically perceive sound frequencies between 20 Hz and 20,000 Hz, with sounds below and above these limits termed infrasound and ultrasound, respectively, although these are not audible to us. Detectable wavelengths correspond to these frequency ranges based on the wave speed in the specific medium.

When waves share the same frequency but travel through different mediums with varying speeds, their wavelengths must differ. This relationship is governed by the equation v=f×λ, where v is the wave speed, f is the frequency, and λ is the wavelength. If the speed changes while the frequency remains constant, the equation requires the wavelength to adjust accordingly. In practical terms, this phenomenon is evident when light passes from one medium to another with different refractive indices, resulting in a change in both its speed and wavelength.

Theoretically, two distinct types of waves, like sound and light, could share the same frequency. However, due to their vastly different speeds—light being significantly faster than sound—their wavelengths would differ considerably. Utilizing the equation v=f×λ, with a constant frequency, the wave with a higher speed (light) would exhibit a much longer wavelength compared to the slower wave (sound). In practice, it's unusual for sound and light frequencies encountered in daily life to align precisely due to their inherent nature and the disparities in their propagation speeds.

Adjusting the source of a wave, especially sound waves, directly impacts its frequency. For example, plucking a guitar string at different rates changes the pitch produced, corresponding to a change in frequency. Using the equation v=f×λ, where v is the wave speed, f is the frequency, and λ is the wavelength, any change in the frequency caused by altering the source will lead to an inversely proportional change in the wavelength, assuming the wave speed remains constant.

The speed of a wave depends on the characteristics of the medium it travels through. Waves, such as sound and light, move differently in different materials. For example, sound travels faster in denser mediums like solids compared to gases because particles in solids are closer together. When a wave enters a denser medium, like light passing from air to glass, its speed decreases. Keeping the frequency constant, the equation v=f×λ holds true, where v is the wave speed, f is the frequency, and λ is the wavelength. As the speed changes due to the medium, the wavelength also adjusts accordingly.