Which one of the following characteristics of sound depends on amplitude of vibration ?

Options

A. Speed
B. Pitch
C. Loudness
D. Quality

Explanation

To solve the question regarding which characteristic of sound depends on the amplitude of vibration, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Characteristics of Sound**:
- Sound has several characteristics, including speed, pitch, quality, and loudness. We need to identify which of these is influenced by the amplitude of vibration.

2. **Define Each Characteristic**:
- **Speed**: The speed of sound is determined by the medium through which it travels and does not depend on amplitude.
- **Pitch**: Pitch is related to the frequency of the sound wave. Higher frequency results in a higher pitch, and it is not affected by amplitude.
- **Quality**: Quality (or timbre) refers to the complexity of sound waves and is determined by the waveform. It does not depend on amplitude.
- **Loudness**: Loudness is the perception of sound intensity and is directly related to the amplitude of the sound wave.

3. **Analyze the Relationship Between Amplitude and Loudness**:
- Loudness is proportional to the square of the amplitude of vibration. This means that as the amplitude increases, the loudness also increases.

4. **Conclude the Answer**:
- Since loudness is the only characteristic that depends on the amplitude of vibration, we conclude that the answer to the question is **loudness**.

### Final Answer:
The characteristic of sound that depends on the amplitude of vibration is **loudness**.

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