What causes sound ?

Explanation

**Step-by-Step Text Solution:**

1. **Understanding Sound Production**: Sound is produced by the vibrations of objects. These vibrations can be rapid and are typically associated with elastic bodies.

2. **Vibration Mechanism**: When an elastic body vibrates, it moves back and forth quickly. This rapid movement creates pressure waves in the surrounding medium (like air), which we perceive as sound.

3. **Example of Sound Production**: A common example is the human voice. When we speak, our vocal cords vibrate. These vibrations create sound waves that travel through the air to reach the listener's ears.

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