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    (Original post by NatashaG)
    Can someone please explain to me transistors I don't get them I have read the revision guide a million times and I dont undersatnd why they are useful please help me
    Transistors are basically switches that are controlled by electricity, and they are more useful because they are much smaller than a manual switch, and you can easily put it into circuit boards, leading to smaller devices and circuits (miniaturisation).
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    (Original post by NatashaG)
    Can someone please explain to me transistors I don't get them I have read the revision guide a million times and I dont undersatnd why they are useful please help me
    No voltage = No current passes through

    Small voltage = gate closes, current passes through

    Big voltage = damage

    They're used to.make logic gates as well..
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    Could someone do a low-down on what's came up in the last few papers please? My computer is taking ages to download just one paper -.- :/ thanks


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    (Original post by BP_Tranquility)
    Yeah, same here! Still can't believe that the atom model we're taught in schools for years is "obsolete" though lol :rolleyes:...Hopefully A Levels won't have be like this
    What do you mean they're obsolete?
    (I know what Obsolete means...just wondering what you mean by it in terms of the model)


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    (Original post by BP_Tranquility)
    Yeah, same here! Still can't believe that the atom model we're taught in schools for years is "obsolete" though lol :rolleyes:...Hopefully A Levels won't have be like this
    I know someone who did Chemistry at uni and apparently they tell them to forget everything they learnt about it at A Levels because it's completely different too haha.

    My chemistry teacher says it's a bit like driving a car. First you need to learn how to drive the car (GCSE) and then you're taught how the car drives.
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    (Original post by Knowing)
    Transistors are basically switches that are controlled by electricity, and they are more useful because they are much smaller than a manual switch, and you can easily put it into circuit boards, leading to smaller devices and circuits (miniaturisation).
    (Original post by L'Evil Fish)
    No voltage = No current passes through

    Small voltage = gate closes, current passes through

    Big voltage = damage

    They're used to.make logic gates as well..

    Thanks

    So like they allow things to switch on without you pressing a switch is this the right idea?
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    (Original post by BP_Tranquility)
    :rolleyes:...Hopefully A Levels won't have be like this
    Apparently they are, once you do a degree in a subject you took at A Level you'll see that most of the stuff wasn't detailed enough, and as you go through each year in uni you find the stuff you learned the previous year still wasn't completely right. That's just what I've heard though
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    (Original post by benwalters1996)
    Could someone do a low-down on what's came up in the last few papers please? My computer is taking ages to download just one paper -.- :/ thanks


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    This is the first time this specification has been sat...
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    (Original post by benwalters1996)
    What do you mean they're obsolete?
    (I know what Obsolete means...just wondering what you mean by it in terms of the model)


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    I'm glad you asked- the model we're taught at school is called the Bohr model and it is outdated. We're taught that electrons orbit the nucleus of an atom which have circular orbits, but it is actually much more complicated than that because you can't predict both the speed the electron is travelling at and its position at the same time (since it violates the Heisenberg Uncertainty Principle). The Bohr Model was also created and its predictions are based on Hydrogen (which only has one electron) so its predictions for larger atoms that have more than one electron aren't completely accurate! Essentially, this model has now been replaced by Quantum Mechanics which provides the best explanation/predictions so far :cool:
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    (Original post by NatashaG)
    Thanks

    So like they allow things to switch on without you pressing a switch is this the right idea?
    Yeah, I guess use voltage instead to turn on and off
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    (Original post by andersson)
    This is the first time this specification has been sat...
    Previous spec


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    (Original post by cameron262)
    I know someone who did Chemistry at uni and apparently they tell them to forget everything they learnt about it at A Levels because it's completely different too haha.

    My chemistry teacher says it's a bit like driving a car. First you need to learn how to drive the car (GCSE) and then you're taught how the car drives.
    (Original post by andersson)
    Apparently they are, once you do a degree in a subject you took at A Level you'll see that most of the stuff wasn't detailed enough, and as you go through each year in uni you find the stuff you learned the previous year still wasn't completely right. That's just what I've heard though
    So, we have to constantly relearn new things? Well...I guess that's better than just knowing the wrong information... Oh well, it should be fun (hopefully) :cool:
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    (Original post by NatashaG)
    Thanks

    So like they allow things to switch on without you pressing a switch is this the right idea?
    'So they like turn things on and off' <---can just imagine the response to the 6 mark question now *cheeky grin*


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    (Original post by benwalters1996)
    'So they like turn things on and off' <---can just imagine the response to the 6 mark question now *cheeky grin*


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    HAHA...what does a resistor do? it like makes the bull dim and stuff
    Explain how gamma radiation is used to treat cancer? it like kills the cancer and stuff

    I'm great at thorough explanations!!!
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    (Original post by benwalters1996)
    Previous spec


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    But any 6 markers now won't be dependent on the old 6 markers, because they're a different spec :cool:

    Edit: There aren't any 6 markers in the old spec, which makes looking at old papers even more pointless :lol:

    thanks BP
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    (Original post by andersson)
    But any 6 markers now won't be dependent on the old 6 markers, because they're a different spec :cool:
    There aren't any six markers in the old spec
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    (Original post by BP_Tranquility)
    There aren't any six markers in the old spec
    Edited
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    I meant to see what kind of topics they like to ask about


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    How far is everyone with revision?
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    Haven't even learnt stuff

    Gonna have to do an all day job
 
 
 
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