Doppler Effect Calculator

Formula

The formula to calculate the observed frequency of the Doppler effect is:

\[ \text{f} = \text{f0} \times \frac{\text{v} + \text{vr}}{\text{v} + \text{vs}} \]

Where:

\(\text{f}\) is the observed frequency
\(\text{f0}\) is the emitted frequency
\(\text{v}\) is the wave velocity
\(\text{vr}\) is the receiver velocity
\(\text{vs}\) is the source velocity

What is the Doppler Effect?

The Doppler effect describes the change in frequency of a wave in relation to an observer who is moving relative to the wave source. When waves are emitted from a moving object, the observed frequency changes for the observer. This effect is commonly experienced with sound waves, such as the change in pitch of a passing siren.

Example Calculation

Let's consider an example:

Emitted Frequency (f0): 500 Hz
Wave Velocity (v): 340 m/s
Receiver Velocity (vr): 10 m/s
Source Velocity (vs): 20 m/s

Using the formula to calculate the observed frequency:

\[ \text{f} = 500 \times \frac{340 + 10}{340 + 20} = 500 \times \frac{350}{360} \approx 486.11 \text{ Hz} \]

This means that the observed frequency (f) is approximately 486.11 Hz.