Car Horn (500 Hz) Approaching at 27 m/s (97 km/h)
A car horn at 500 Hz travelling at 27 m/s toward a stationary observer is heard at about 543 Hz.
How to use this tool
- Enter source frequency fā, source velocity vā, observer velocity vā and wave speed v in the fields above.
- Results update instantly as you type ā or click Calculate.
- Read your observed frequency and the full breakdown beneath it.
At highway speed, a car horn shifted up by about 43 Hz sounds noticeably sharper than when the car is stationary.
Frequently asked questions
- What is the speed of sound used here?
- 343 m/s at 20 Ā°C in air at sea level. It varies with temperature: roughly v ā 331 + 0.6ĆT(Ā°C) m/s.
- Does the Doppler effect apply to light too?
- Yes, but the relativistic formula must be used. The astronomical redshift of distant galaxies is a Doppler-related phenomenon.