2006 MC 12 and 2007 13 (1 Viewer)

dolbinau

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Can someone explain 2006 question 12 and 2007 question 13?

I don't get either of them (I assume they must be a similar concept too)...SuccessOne answers don't help me.

thanks
 

alez

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havent done 2007 yet but 2006 q12
basically, if a charged particle is moving parallel to a magnetic field, there is no force acting on it
if you look at the equation F=qvBsinΘ, B does affect F
v affects F, but if it is parallel, Θ=90, so F=0
 

alez

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ok checked out 2007
A and B are both parallel, so rule them out. if you draw a diagram with a wire and the magnetic field around it, then use rhpr. (because the mag field is circular, just draw a tangent at any point) then flip the direction you come up with as electrons are negative
hope that made some sense
 

shanks27

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2006 Q12 answer is C, because using the right hand rule a charged particle's force only comes when it is perpendicular to the field. If a charge particle enters a magnetic field parallel to the field there is no effect on it.

2007 Q13 Answer is C, because when the current flows in the wire a magnetic field is created, using the right hand grip rule. BEcause the electron expierences a force in the same direction, its magnetic field must add to the one created by the current in the wire. So once again if u look at the right hand palm rule for the forces to add together, the electron must be travelling perpiduclar to the magnetic field (to expierence a force) and towards it (to add to the force of the current). for that question it is good to draw a diagram and jst put the current in then work backwards to work out which way the electron is going

Hope it helps
 

dolbinau

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Got 06 bur not 07, so frustrating!

I get the magnetic field around the wire, but that's about it. I don't know how to use the right hand palm rule on a circular magnetic field :S. WHere do I draw a tangent?
 

alez

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anywhere
draw it as if the wire is out of page, then the mag field will be a circle
then draw a tangent anywhere on the circle
 

samwell

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dolbinau said:
Can someone explain 2006 question 12 and 2007 question 13?

I don't get either of them (I assume they must be a similar concept too)...SuccessOne answers don't help me.

thanks
The 06 qsn was a trick 4 pple who did not look care fully e.g ME yh its perpendicular to the current carrying conductor as everyone just said...lol
 

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