What is 'frequency' in the context of light?

In the context of light, 'frequency' refers to the number of waves that pass a particular point in one second. This is an essential concept in understanding how light behaves and interacts with materials. Frequency is measured in hertz (Hz), which indicates cycles per second. It is a critical parameter that, along with wavelength, defines the nature of light waves.

When light is emitted, it travels in waves, and the frequency of these waves determines the light's color in the visible spectrum. For example, visible light encompasses a range of frequencies, with red light having a lower frequency compared to blue light, which has a higher frequency. This frequency also plays a key role in determining the energy of the light; higher frequency light carries more energy.

Understanding frequency is fundamental in optics, as it relates directly to concepts like absorption, reflection, and transmission of light through various media. When studying how light interacts with different lenses or materials, frequency becomes a crucial factor in predicting and explaining behaviors such as refraction and diffraction.