ATAR Notes: Forum
VCE Stuff => VCE Science => VCE Mathematics/Science/Technology => VCE Subjects + Help => VCE Physics => Topic started by: shokstar on November 08, 2010, 09:18:07 pm
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Can anyone give me an explanation into induced current in terms of its direction? I've had a go at one which im almost certain is completely incorrect:
'A moving conductor in a magnetic field creates an electromotive force that is at right angles to the magnetic field.
Hence, the negative charges are pushed in one direction and positive charges are moved in the other direction and hence theres a seperation of charges which creates a current, in the direction of the positive charges'
Help me out here... :(
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This is tricky, but you just have to remember that a conventional current (the flow of positive charge) can be found by applying Lenz's law.
And ye - the definition you provided is essentially the definition of a current - where positive and negative charge are separated.
You can use the Right hand slap rule (with finger as the field, velocity as the force and thumb as the current) to find the direction of current. Take that answer, and reverse it - and walla you have the induced current!
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This is tricky, but you just have to remember that a conventional current (the flow of positive charge) can be found by applying Lenz's law.
And ye - the definition you provided is essentially the definition of a current - where positive and negative charge are separated.
You can use the Right hand slap rule (with finger as the field, velocity as the force and thumb as the current) to find the direction of current. Take that answer, and reverse it - and walla you have the induced current!
X.x yea this single concept took me a whole lesson of staring at the page to understand but I haven't seen it in a prac exam yet.
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This is tricky, but you just have to remember that a conventional current (the flow of positive charge) can be found by applying Lenz's law.
And ye - the definition you provided is essentially the definition of a current - where positive and negative charge are separated.
You can use the Right hand slap rule (with finger as the field, velocity as the force and thumb as the current) to find the direction of current. Take that answer, and reverse it - and walla you have the induced current!
X.x yea this single concept took me a whole lesson of staring at the page to understand but I haven't seen it in a prac exam yet.
Try STAV
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Stav 2010.
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=/ Looking at it (This was one of the first trials I did)...is this like question 9?
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=/ Looking at it (This was one of the first trials I did)...is this like question 9?
Something with a moving car and a radio wire - if I remember correctly. . .
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Lol for that question i know how to get tip but what explanation do u give?
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Copy pasted from what i Wrote 0.o
"Vehicle travel east --> charged particles travel east. Earth's field is directed towards the North. Thus magnetic force on electrons, according to right-hand slap rule, are directed into the page. Hence base has build up of electrons, becoming the negatively charged end. Thus tip is positive end."
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Lol!thats it? aahh coool thanks!
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would u have to write something like electrons moving east =positive charges moving west? thats the direction of thumb?(west)?
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would u have to write something like electrons moving east =positive charges moving west? thats the direction of thumb?(west)?
I guess you can say that, but I don't like it because it's technically not correct X.X It's using the notion of conventional current when it's not correct as only electrons are moving throughout a complete circuit rather than positive charges.
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Well :P then i wont write it :D .