A vibration state in the above vibrating is substantially identical to another vibration state where {HEAD ~ a transmission surface} having {TAIL ~ a larger area} vibrates 
A vibration state in the above vibrating is substantially identical to another vibration state where { HEAD ~ a transmission surface } having { TAIL ~ a larger area } vibrates
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH