The disappearance of sound is caused by blood flowing freely. The blood flows freely because there is no constricted artery.
The absence of turbulence.
The disappearance of a wave into a medium is called absorption.
Reflected
as you expel air from your rectum the air reverberates through your sphincter causing the sound. This sound can be further amplified by the air reverberating your butt cheeks :)
A similar noise can be heard coming out of the electric meters attached to ... causes expansion and contraction of the wire, producing sound.
When taking blood pressure there are two readings, eg 120/70. The first reading (120) is the systolic blood pressure and the second reading (70) is the diastolic blood pressure. The systolic blood pressure is always higher than the diastolic.The systolic reading is when the heart muscle is contracting, pushing blood through the arteries, therefore creating more pressure (hence the higher number) in the arteries.The diastolic reading is when the heart is relaxed and refilling with blood, ready for the next beat, therefore exerting less pressure on the arteries (hence the lower number)
There will be no systolic sound if blood is flowing freely. This occurs when there is no measurable constriction of an artery.
the systolic sound is caused by ventricular contraction
systolic
Rapid potassium infusion causes diastolic and not systolic cardiac arrest.
Hydrocarbon eating bacteria
Systolic
components
The systolic pressure is measured at the first Karotkoff sound (stage I), it is the first tapping noise that you hear with a stethoscope when taking a manual blood pressure.
diastolic pressure
it calms you and causes your blood to slow down.
Ideally ... the first sound is the systolic pressure, and the loudest sound is the diastolic. Note that both are artifacts of turbulence, since smooth flow is soundless.
Diastolic is more likely to be due to a real problem, where systolic may be harmless. However, there's no rule about which is worse...they have different possible causes, both bad and not so bad.