Can Sound Travel Without Air? Watch the Demo! Video Watch time Under 1 minute February 16, 2025 Image Why can't we hear this alarm clock in a vacuum chamber? Museum Science Educator Lauren demonstrates how in a vacuum, sound cannot travel. This is because there are no air molecules to push against and vibrate, and we need moving air to vibrate our eardrums in order to hear. Watch as we test this inside a vacuum chamber! This experiment explains why in space, no one can hear you scream! Topics Physics Share