Final answer:
In courtroom etiquette, a single tap of the judge's gavel typically signals the audience to sit down, maintaining order and respect during legal proceedings.
Step-by-step explanation:
The typical protocol in a courtroom setting indicates that when a judge's gavel is tapped once, it is the signal for the audience to be seated. A single tap of a gavel can carry various meanings depending on the context, but in this instance, it serves as a clear instruction for the courtroom participants to sit down, adding gravity and ceremony to the proceedings. This practice helps maintain order and respect for the judicial process.