1. What is an Observed Frequency Calculator?

Definition: This calculator determines the observed frequency of a wave when there is relative motion between the source and observer (Doppler Effect).

Purpose: It helps in physics, acoustics, and astronomy to understand how motion affects perceived frequency.

2. How Does the Calculator Work?

The calculator uses the Doppler Effect formula:

Where:

• \( f_o \) — Observed frequency (Hz)
• \( v \) — Wave speed (m/s)
• \( v_o \) — Observer velocity (m/s)
• \( v_s \) — Source velocity (m/s)
• \( f \) — Source frequency (Hz)

Explanation: The formula accounts for relative motion between source and observer, changing the perceived frequency.

3. Importance of Doppler Effect Calculation

Details: Understanding frequency shifts is crucial in applications like radar speed guns, medical ultrasound, and astronomical redshift measurements.

4. Using the Calculator

Tips: Enter wave speed (e.g., 343 m/s for sound in air), velocities (positive if moving toward each other), and source frequency. Wave speed must be greater than source velocity.

5. Frequently Asked Questions (FAQ)

Q1: What's a typical wave speed for sound?
A: About 343 m/s in air at 20°C, but varies with medium and temperature.

Q2: How do I indicate direction of motion?
A: Use positive values for motion toward each other, negative for motion away.

Q3: What if source is stationary?
A: Set source velocity to 0. If observer is stationary, set observer velocity to 0.

Q4: Why can't wave speed equal source velocity?
A: This would create division by zero in the formula (sonic boom scenario).

Q5: Does this work for light waves?
A: For light, use relativistic Doppler formulas as speeds approach light speed.