Sometimes a studio audience is directed to applaud either by a sign, signal, or a “conductor” of sorts. Sometimes during, for instance, a presentation the presenter makes it clear they want to speak and will placate the audience with a gesture, cue, or sound. And sometimes the audience just slowly dies out on its own. Often there will be a general unspoken consensus that it is time to stop and they will fade out on their own, usually after about 5-8 seconds is the limit audiences reasonably applause given the setting and social expectations of the venues.
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