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ocatal

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Looking through my textbook. It says "A photocell is a device that uses the photoelectric effect. These devices include photovoltaic, or solar cells."
 
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So ironic, I knew photocells perfectly but I crammed solar cells before the exam and I wrote about solar cells.
Good work Abdullah, good work...
 

Fizzy_Cyst

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my teacher with a PHD said that it is... awks for you Meno.
Actually, pretty awks for your PhD teacher when he is incorrect.

Have a look at where that the dot point concerning photocells in the syllabus.. Before semiconductors..

Hmmmmmmm....

I wouldnt be surprised if they end up accepting both
 
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Menomaths

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Looking through my textbook. It says "A photocell is a device that uses the photoelectric effect. These devices include photovoltaic, or solar cells."
Solar cells use the photoelectric effect, but they are different to photoelectric cells

For solar cells I recall, you have to get an electron from the n type side liberated and then it goes through some depletion zone then through an external circuit whereas photocells it's when an incident ray strikes the emitter and the electron that is liberated goes to the collector then through the external circuit or something like that
 

superSAIyan2

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basically i wrote: a photocell consists of an anode and a photosensitive cathode in a highly evacuated glass tube. When light of a frequency higher than the cathode's threshold frequency strikes the cathode it emits free electrons by the photoelectric effect. The electrons are accelerated as a focussed beam towards the positive anode due to a applied potential difference, this initiates a photocurrent. The current can be amplified to do work in an external circuit; e.g. power a lamp.

Isnt photocells easier than solar cells?
 

Menomaths

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basically i wrote: a photocell consists of an anode and a photosensitive cathode in a highly evacuated glass tube. When light of a frequency higher than the cathode's threshold frequency strikes the cathode it emits free electrons by the photoelectric effect. The electrons are accelerated as a focussed beam towards the positive anode due to a applied potential difference, this initiates a photocurrent. The current can be amplified to do work in an external circuit; e.g. power a lamp.

Isnt photocells easier than solar cells?
Much easier
 

panda15

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Yeah heaps disappointed
That there was no projectile
This! I just realised this!
What the hell? Why are we the year that gets no projectiles? They're the easiest marks in the paper...
 

omgiloverice

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bad luck for me I only realised that photocells aren't solar cells at the very last 30 seconds... I remember the hsc exams once made a mistake on photocells and solar as well. But I can't seem to find the question...
 

Web Addict

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Actually, pretty awks for your PhD teacher when he is incorrect.

Have a look at where that the dot point concerning photocells in the syllabus.. Before semiconductors..

Hmmmmmmm....

I wouldnt be surprised if they end up accepting both
Lol. I hope the Board of Studies don't accept both. It gives me a slight chance to get a Band 6.

No projectile :mad:
Yeah, wtf? I love projectile motion. At least there were loads of calculations.
 
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anomalousdecay

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Photocells are pretty much the thermionic equivalent of solar cells.

It consists of 2 electrodes embedded within a vacuum tube. A large cathode covered in photosensitive material, from which photoelectrons can be emitted when subject to sunlight.
Wow. I do Age of Silicon and didn't even know that the structure is different.

Damn Jacaranda. Says that photocells can be p-n junctions.

These are photocells. PHOTOCELLB.jpg

According to Jacaranda, what you are referring to is "photo-conductive cells".

Its time for Board of studies to assess the validity of Jacaranda. That should pop-up next year in my opinion.

Otherwise, I just lost the 5 marks that I thought I smashed.

Far-out.
 
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RealiseNothing

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If jacaranda is saying that photocells includes solar cells, and many students write about solar cells because photocells don't get taught (I learnt photocells as being solar cells), then surely something would have to be done?
 

anomalousdecay

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If jacaranda is saying that photocells includes solar cells, and many students write about solar cells because photocells don't get taught (I learnt photocells as being solar cells), then surely something would have to be done?
2014 HSC 3 marks:

"Explain how you assessed the validity of data from textbooks."

Do you have Jacaranda? Have a quick look at it. If not, pm me.

Ironically, Jacaranda is my source for Age of Silicon and LDRs are shown as pn junctions. Look at the picture above.

Honestly, if the person who wrote about photocells wrote age of silicon, then we can can get the marks.

Anyway, even if we did stuff up, we would still get two marks for addressing that dot-point of the syllabus maybe?
 

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