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What is Frequency of 1st hea sound and explain in detail?
The first sound has a duration of about 0.15 s and a frequency of 25-45 Hz. It is soft when the hea rate is low because the ventricles are well filled with blood and the leaflets of the AV valves float together before systole.Ref: Ganong&;s Review of medical physiology 25th edition. Page: 542