Drinking cranberry juice is a fairly well-known and natural way to both help prevent urinary tract infections, as well as help speed the recovery process when a UTI develops. Just drinking two 4-ounce glasses of cranberry juice daily is often enough to both prevent a UTI and speed recovery when an infection does develop.
Ultrasound waves travel faster through a stiff medium, such as bone. In echocardiography, the velocity of sound is assumed to be approximately 1,540 m/sec (or 1.54 m/msec). Sound waves travel through the air with speed of 330 m/s.
Our Living Language : Many people use simple ultrasound generators. Dog whistles, for example, produce tones that dogs can hear but that are too high to be heard by humans. Sound whose frequency is higher than the upper end of the normal range of human hearing (higher than about 20,000 hertz) is called ultrasound.