📚 Topic Summary
The Doppler Effect describes the change in frequency of a wave (like sound or light) when the source of the wave and the observer are moving relative to each other. Imagine a car honking as it drives past you; the pitch sounds higher as it approaches and lower as it moves away. A frequency shift simulation allows you to visualize and understand how the relative speeds affect the observed frequency.
🧮 Part A: Vocabulary
Match the term with its correct definition:
| Term |
Definition |
| 1. Wavelength |
A. The number of waves passing a point per second. |
| 2. Frequency |
B. The change in frequency due to relative motion. |
| 3. Velocity |
C. The distance between successive crests of a wave. |
| 4. Doppler Shift |
D. The speed of an object in a given direction. |
| 5. Observer |
E. The person or instrument detecting the wave. |
Answers: 1-C, 2-A, 3-D, 4-B, 5-E
✍️ Part B: Fill in the Blanks
The Doppler Effect is most noticeable when the source of a wave is moving at a significant __________ relative to the __________. The __________ frequency is observed when the source is moving towards the observer, and a __________ frequency is observed when the source is moving away. This phenomenon can be described mathematically using the following formula: $f' = f(\frac{v \pm v_o}{v \mp v_s})$, where $f'$ is the __________ frequency, $f$ is the __________ frequency, $v$ is the speed of the wave, $v_o$ is the speed of the __________, and $v_s$ is the speed of the __________.
Answers: speed, observer, higher, lower, observed, original, observer, source
🤔 Part C: Critical Thinking
Explain how the Doppler Effect is used in real-world applications, such as radar speed guns or medical imaging. Provide at least two specific examples.