The difference between a musical sound and noise is

Options

A. amplitude
B. loudness
C. vibration
D. all of these

Explanation

To solve the question regarding the difference between a musical sound and noise, we can break it down step by step:

### Step 1: Understand the Definition of Musical Sound
Musical sound is produced by regular vibrations. This means that the vibrations occur in a consistent and periodic manner, which creates a sound that is harmonious and pleasant to listen to.

### Step 2: Understand the Definition of Noise
Noise, on the other hand, is produced by irregular vibrations. This means that the vibrations do not follow a consistent pattern, resulting in a sound that is often harsh, unpleasant, or jarring to the ears.

### Step 3: Analyze the Options Given
The options provided in the question are:
1. Amplitude
2. Loudness
3. Vibration
4. All of this

### Step 4: Compare the Options with the Definitions
- **Amplitude** refers to the height of the sound wave and does not differentiate between musical sounds and noise.
- **Loudness** is related to how we perceive the intensity of sound, which also does not distinguish between musical sounds and noise.
- **Vibration** is the key difference, as musical sounds arise from regular vibrations while noise comes from irregular vibrations.

### Step 5: Conclusion
Based on the definitions and analysis, the primary difference between musical sound and noise is the nature of the vibrations that produce them. Therefore, the correct answer is **option 3: Vibration**.

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