In physics, wavelength and frequency are two fundamental concepts used to describe waves, including electromagnetic waves such as light.
Wavelength: The wavelength of a wave is the distance between two corresponding points on the wave, usually measured from crest to crest or trough to trough. It represents the spatial extent of one complete cycle of the wave. In the context of light, wavelength refers to the distance between successive peaks or troughs of the electromagnetic wave. Wavelength is typically denoted by the Greek letter lambda (λ) and is measured in units such as meters (m), nanometers (nm), or angstroms (Å).
Frequency: The frequency of a wave is the number of complete cycles (or oscillations) of the wave that occur in one second. It represents how many wave crests pass a given point per unit of time. Frequency is measured in units called hertz (Hz), which represents the number of cycles per second. For example, a frequency of 1 Hz means one cycle per second, while a frequency of 100 Hz means 100 cycles per second.
The relationship between wavelength and frequency is described by the equation:
c = λν
where c is the speed of light in a vacuum, λ (lambda) is the wavelength, and ν (nu) is the frequency. This equation shows that wavelength and frequency are inversely proportional to each other. As the wavelength increases, the frequency decreases, and vice versa. This relationship holds true for all types of waves, including electromagnetic waves like light.
To summarize, wavelength refers to the spatial extent of a wave, while frequency represents the number of cycles of the wave per unit of time. They are related through the speed of the wave, such as the speed of light.