How is a piezoelectric crystal used to generate waves of ultrasound?

A piezoelectric crystal makes use of the peizoelectric effect. This is the production of a voltage when mechanical stress is applied across the material. This occurs only in materials when the unit cells which make up the material have an asymmetric charge distribution when under compression.
The reverse of this is using the crystal to produce waves. This is the reverse peizoelectric effect. This means appying a voltage to the crystal, producing compression. When an alternating current is applied, this gives repeated compression and relaxation of the crystal.
The movement of the face of the crystal will displace air molecules, giving a longitudinal wave, meaning, at the necessary high frequency, ultrasound waves.

DA
Answered by David A. Physics tutor

10032 Views

See similar Physics A Level tutors

Related Physics A Level answers

All answers ▸

Why is the sky blue?


Define Simple Harmonic Motion


A nail of mass 7.0g is held horizontally and is hit by a hammer of mass 0.25kg moving at 10ms^-1. The hammer remains in contact with the nail during and after the blow. (a) What is the velocity of the hammer and nail after contact?


A cannon is fired at 30 degrees from the ground and the cannonball has initial velocity of 15 m/s. What is the height of the highest point the cannonball reaches and how far is this point horizontally from the cannon?


We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

© MyTutorWeb Ltd 2013–2025

Terms & Conditions|Privacy Policy
Cookie Preferences