Sound Waves and Ultrasound Flashcards
What do soundwaves do?
Sound waves cause particles to vibrate backwards and forwards in the direction of the wave.
Why are sound waves a type of pressure wave?
There are areas where the air pressure is different in a sound wave.
What can be used to detect sound?
A microphone.
What can be used to produce sound?
A loudspeaker.
What causes changes in air pressure?
The diaphragm of the loudspeaker vibrating more quickly.
What frequency of sounds can humans hear?
20 - 20,000 Hz
What is an ultrasound?
A sound with any frequency higher than 20,000.
What happens to the particles that the ultrasounds interact with?
The particles vibrate more quickly.
What is ultrasonic cleansing?
Using ultrasound to ‘shake’ the dirt particles of objects.
What is physiotherapy?
Using ultrasound to cause liquid particles in the body to move more quickly and get warmer.
