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Piezoelectric effect? (1 Viewer)

aero135

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hey guys,

i am a bit unsure as to what is the actual definition of the piezoelectric effect.... Is it the AC power supply attached to the crystal produces mechanical vibrations(ultrasound) which is what EXCEL and JACARANDA say or is it the opposite that mechanical vibrations produce a potential difference which is what wikipedia and the net says...

cheers
 

Lukybear

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In ultrasounds its the first one. Because the waves that ultrasounds use are mechanical, hence, manul vibrations are used.
 

sifANDREW

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According to my physics teacher...
Piezo electric effect:
A piezoelectric crystal contains dipole atoms within it. When a piezoelectric crystal is compressed (preassure is applied to both ends) it lines up the dipole atoms, creating a potential difference (used in transducers to receive the refelected signal).

The reverse piezoelectric effect is when a varying potential diference is applied to opposite faces of the piezoelectric crystal. This causes an electric field that will deform the crystal, creating vibrations at the surfaces creating ultrasound.

Hope it helps lol.
 

iMAN2

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According to my physics teacher...
Piezo electric effect:
A piezoelectric crystal contains dipole atoms within it. When a piezoelectric crystal is compressed (preassure is applied to both ends) it lines up the dipole atoms, creating a potential difference (used in transducers to receive the refelected signal).

The reverse piezoelectric effect is when a varying potential diference is applied to opposite faces of the piezoelectric crystal. This causes an electric field that will deform the crystal, creating vibrations at the surfaces creating ultrasound.

Hope it helps lol.
Good explanation. I doubt they would ever require more detail in regards to this concept.
 

miniwaybzz

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hey guys,

i am a bit unsure as to what is the actual definition of the piezoelectric effect.... Is it the AC power supply attached to the crystal produces mechanical vibrations(ultrasound) which is what EXCEL and JACARANDA say or is it the opposite that mechanical vibrations produce a potential difference which is what wikipedia and the net says...

cheers
excel + jacaranda = production of ultrasound
wiki = how reflected waves are analysed
 

impulsebro89

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basically the piezoelectric effect is the conversion of electrical energy into mechanical energy (ultrasound/sound waves) and vice versa.

To produce ultrasound, you put a piezoelectric crystal (a material that basically demonstrates the piezoelectric effect) through an electrical field, which aligns its dipoles and changes the size of the crystal. If you put AC through it, the crystal will expand and contract constantly, because the voltage changes constantly, which vibrates air to produce sound (ultrasound)

Putting ultrasound near a piezoelectric crystal will vibrate it, which realigns the dipoles to produce a net polarity (basically an electric field is produced). If you connect a circuit to the piezoelectric crystal you can produce a current

So yeah in summary the piezoelectric effect works both ways. You should read the physics in focus version of it it's pretty good.

Hope this helps ^.^
 

HoldingOn

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basically the piezoelectric effect is the conversion of electrical energy into mechanical energy (ultrasound/sound waves) and vice versa.

To produce ultrasound, you put a piezoelectric crystal (a material that basically demonstrates the piezoelectric effect) through an electrical field, which aligns its dipoles and changes the size of the crystal. If you put AC through it, the crystal will expand and contract constantly, because the voltage changes constantly, which vibrates air to produce sound (ultrasound)

Putting ultrasound near a piezoelectric crystal will vibrate it, which realigns the dipoles to produce a net polarity (basically an electric field is produced). If you connect a circuit to the piezoelectric crystal you can produce a current

So yeah in summary the piezoelectric effect works both ways. You should read the physics in focus version of it it's pretty good.

Hope this helps ^.^
This thread is 9 years old.
 

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