How Ultrasonic Waves are Produced - Medsinglong

How Ultrasonic Waves are Produced - Medsinglong

Ultrasound has many incredible applications in medical sciences and manufacturing industries. The most important of these is ultrasonic cleaning, which uses ultrasonic waves to propagate in liquids, creating cavitation bubbles that are more thoroughly cleaned than solvents and scrubbed separately.

 

Humans cannot hear ultrasonic waves, but some animals (such as bats) can hear them. Their influence on materials and their abilities may look like magic, but they are pure science. Unlike the normal way of dealing with sounds that usually strike surfaces, ultrasonic waves are made using electrical equipment that vibrates at extremely high frequencies. Crystals of materials such as quartz vibrate very quickly as they pass through - this effect is called "piezoelectricity." When they vibrate, they manipulate the air around them and the fluids they contact, generating ultrasound waves. Devices that use piezoelectric to generate ultrasonic waves are called piezoelectric transducers.

 

Most people can only detect sound frequencies between 16 and 16,000 Hz. Ultrasound has begun to describe sound waves with a frequency greater than 16,000 Hz or 16 kHz. Some insects produce ultrasonic waves up to 40 kHz. Small animals such as cats and dogs hear frequencies up to 30 kHz; bats are known to detect frequencies up to 100 kHz.

 

As it propagates, the sound waves that cause the compression and expansion of the molecules in its surrounding medium are called longitudinal waves. The distance from one compression to the next is called the wavelength of the sound wave. Long-wavelength sound waves pass through small objects in much the same way that waves pass through small objects. On the other hand, short wave sound waves tend to be diffracted or scattered by objects of comparable size.