TRY THIS Position your ears between the 2 ends and close your eyes. Ask a friend to use the stick to tap the tube at different points. Locate the tapping points by listening to the sound?
WHAT IS HAPPENING The output sounds from both ends arrive at each ear at slightly different times. Your brain uses this difference to decide where the tap was made. If the sounds arrive at the same time, they must have come from tapping the midpoint of the tube. Detecting such taps requires very sensitive ear-brain co-ordination, given the very close arrival times at the ears. Exactly how such small time differences are detected is unknown. The brain and ears work together in similar ways to interpret the many sounds and their sources around us. |
.jpg)
PS–48 
