Final answer:
The first music video played on MTV at its launch was "Video Killed the Radio Star" by The Buggles, symbolizing the new era of music consumption.
Step-by-step explanation:
The first music video played on MTV when it launched on August 1, 1981, was the song "Video Killed the Radio Star" by The Buggles. This song was particularly fitting as an inaugural video, as it thematically concerned the impact of television on radio, paralleling the emergence of MTV as a new force in the music industry. The channel then represented a significant shift in how music was consumed and marketed, with music videos becoming a crucial part of an artist's release strategy.