Science & Technology Quiz 2: The one with the catchy title.
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Explain the properties attached to a pyroelectric substance, and why some materials have those properties.
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I assume a pyroelectric substance conducts electricity better at high temperatures. That may be due to an electron configuration at high temperatures that allows better electron movement, and thus greater conductivity.
A pyroelectric substance is a substance, that builds up an electric field if it is heated. It is caused because of termal expansion in a crystal with a missing symmetry (IIRC it was a missing inversion center) causes charge seperation and an electric field.
Mise
isle of lucy
Surely one of those answers is right...?
No, it only works with digital cameras
"Ghost imaging is the copying of the contents of a computer's hard disk into a single compressed file or set of files (referred to as an image) so that the contents of the hard disk, including configuration information and applications, can be copied to the hard disk of other computers or onto an optical disc for temporary storage." http://searchmobilecomputing.techtarget.com/sDefinition/0,,sid40_gci214413,00.html
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You're not supposed to look up the answer...
Apparently Wikipedia directs you to different topics, when entering "Ghost imaging" and "Ghost Imaging" 
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Sorry, my internet has been down recently, and yes, uppi was correct for those who care.
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Sounds like jargon. Something to do with entanglement?
Mise
isle of lucy
I remember my flatmate telling me about it, but I don't at all remember what it was...
Basically everything in physics is jargon.
Yes, it was first discovered using entanglement, but entanglement isn't necessary. The quality will improve with entaglement, though.
It has been 72 hours, so I'll solve:
Ghost imaging is making an image of an object with a CCD chip that only captures light that never interacted with the object at all.
What you need is two light beams that are correlated in some way. They can be entangled, they can be from the same light source, you could have been doing the same things with it, there just needs to be a correlation. One of the beams is directed at the object and then captured by a "bucket" detector (A detector that just counts photons without any spatial resolution). Your other beam goes to the CCD chip. When you then combine the results from the detector and the camera and can construct an image of the object.
This effect was first discovered with entangled photons and that way you get the best signal-to-noise ratio, but it has since been shown, that you can also do this with classical light, that is correlated.
Open floor.
Ghost imaging is making an image of an object with a CCD chip that only captures light that never interacted with the object at all.
What you need is two light beams that are correlated in some way. They can be entangled, they can be from the same light source, you could have been doing the same things with it, there just needs to be a correlation. One of the beams is directed at the object and then captured by a "bucket" detector (A detector that just counts photons without any spatial resolution). Your other beam goes to the CCD chip. When you then combine the results from the detector and the camera and can construct an image of the object.
This effect was first discovered with entangled photons and that way you get the best signal-to-noise ratio, but it has since been shown, that you can also do this with classical light, that is correlated.
Open floor.
SS-18 ICBM
Oscillator
Give me an example of a synport and an antiport.
Perfection
The Great Head.
Sidney and Topeka?
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