Tag: physics

Ultrasound beam is more directional and can be aimed towards any target just like a torch. Thus ultrasonic waves remain undeviated over long distances

Ultrasound waves can penetrate into matter to a large extent because they have very high frequency. They have frequency higher than 20,000Hz.

Ultrasound has higher frequency than the audible range sound, and thus it has shorter wavelength. Due to this short wavelength, it becomes easy for it to interact(reflect, disperse) from small objects in its path.

Among the above, high frequency is property of ultrasound.

Ultrasonic waves are not harmful but just humans cant hear those frequency.

Ultrasonics, vibrations of frequencies greater than the upper limit of the audible range for humans, that is, greater than $20kHz$.

The frequencies used in ultrasonic diagnosis are in the range of 1 to 10 MHz. The speed of sound waves in the tissues of the human body averages about 1540 m/s (close to that for water). So, the wavelength of a 1 MHz wave is about $λ = v/f = 1540/1∙106 = 1.5∙10–3 m = 1.5 mm$.

Ultrasound can be used in 

Infrasound, sometimes referred to as low-frequency sound, is sound that is lower in frequency than 20 Hz or cycles per second, the "normal" limit of human hearing. So 5Hz is infrasonic.