Gyakoriságváltozás

Gyakoriságváltozás is a Hungarian term that translates to "frequency change" or "change in frequency." In its most common application, it refers to the phenomenon of the perceived pitch of a sound changing due to the relative motion between the sound source and the observer. This is a direct manifestation of the Doppler effect.

The Doppler effect explains why the pitch of a siren sounds higher as it approaches and lower as it moves away. This occurs because the sound waves emitted by the approaching source are compressed, leading to a shorter wavelength and thus a higher frequency. Conversely, as the source recedes, the sound waves are stretched out, resulting in a longer wavelength and a lower frequency.

While most often associated with sound waves, the concept of frequency change applies to other types of waves as well, including light waves. In astronomy, the redshift (a decrease in frequency) of light from distant galaxies indicates that they are moving away from us, while blueshift (an increase in frequency) suggests movement towards us. This observation is a cornerstone of our understanding of the expanding universe.

The term gyakoriságváltozás can be used in various contexts where a shift in the rate or occurrence of something is observed, not exclusively limited to wave phenomena. However, its primary and most widely understood meaning is tied to the Doppler effect.