Orientation

Principle

Explain how you can tell where the tube is being tapped. If you tap closer to the right ear, the sound has to travel a shorter distance to the right ear than to the left ear and therefore gets there faster. Why do you need both ears to perceive which direction a sound is coming from? The direction from which a sound comes can be detected because the sound is more likely to arrive at the ear that is facing the source of the sound. If you only listen with one ear, you cannot tell the difference.