A vibrating tuning fork is placed over the mouth of a burette filled with water. The tap of the burette is opened and the water level gradually starts falling. It is found that the sound from the tuning fork becomes very loud for a particular length of the water column.
Name the phenomenon taking place when this happens.

Explanation

To solve the question, we need to identify the phenomenon that occurs when the sound from the tuning fork becomes very loud for a particular length of the water column in the burette.

### Step-by-Step Solution:

1. **Understanding the Setup**: A vibrating tuning fork is placed over the mouth of a burette that is filled with water. As the water level decreases, the length of the air column above the water changes.

2. **Identifying the Sound**: The tuning fork produces sound waves that travel through the air. The sound waves can resonate with the air column in the burette.

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