Question

In which diagnostic system, Piezoelectric effect, and Reverse Piezoelectric effect are involved?
A) EEG
B) CAT
C) USG
D) MRI

Answer 1

Hint: The piezoelectric effect converts kinetic or mechanical energy, due to crystal deformation, into electrical energy. This is how ultrasound transducers receive the sound waves.

Complete answer:
The transducers which are used in the ultrasound technique work on this phenomenon. The Piezoelectric effect refers to applying an electric field to a crystal. This causes the realignment of the internal dipole structure. This rearrangement results in the crystal to lengthen or contract or change the shape. The process converts electrical energy into kinetic or mechanical energy. The conversion of kinetic or mechanical energy is called the reverse piezoelectric effect. This is caused due to crystal deformation.
Ultrasound transducer produces and detects the ultrasound, which is capable of sending an ultrasound and then the same transducer can detect the sound and convert it to an electrical signal for diagnosing, a piezoelectric crystal has an alternating current applied across it to produce ultrasound. The piezoelectric crystal increases and decreases that depends on the voltage running through it. Running an alternating current through it causes it to vibrate at a high speed and to produce ultrasound. This conversion of electrical energy to mechanical energy is known as the piezoelectric effect. The sound then rebounds off the object under research. In this way, the ultrasonographic technique uses piezoelectric and reverse piezoelectric effects.

Thus, option C is the correct option.

Notes: The sound that hits the piezoelectric crystal and has the bounce-back effect that causes the mechanical energy produced from the sound vibrating the crystal to be converted into electrical energy.