Name the quantity which determines loudness, pitch and quality of a sound.

Explanation

To answer the question regarding the quantity that determines loudness, pitch, and quality of sound, we can break it down into three parts:

### Step 1: Understanding Loudness
- **Loudness** is determined by the **amplitude** of the sound wave. The amplitude refers to the maximum displacement of particles in the medium through which the sound is traveling.
- The relationship is such that loudness is directly proportional to the square of the amplitude. This means that as the amplitude increases, the loudness of the sound also increases.

### Step 2: Understanding Pitch
- **Pitch** is determined by the **frequency** of the sound wave. Frequency is defined as the number of complete cycles (crests and troughs) of the wave that occur in one second.
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