How did Welles capture the attention of people in the audience who may have been doing other things when his broadcast of The War of the Worlds began?

He made an adaptation that made the beginning shorter and less tiring for the audience, in addition, he introduced a song that was commonly played on popular radio programs.

Explanation:

Orson Welles transmitted the work "war of the worlds" in 1938, at that time science fiction was very unpopular and it would be a real challenge to capture people's attention for the exhibition. That was when Welles had the brilliant idea of adapting the beginning of the book for its transmission. So the beginning would be less tiring, but understandable and would have a more attractive pace for listeners. Then he realized that he could get people's attention more efficiently, that way would be by adding a common song on popular radio programs, which would soon draw the attention of everyone who was listening.