Magnetic Force on moving charges




1) Thumb - direction of moving charge (Left - Right +)


3) 4 fingers - Flux Direction

4) Palm - direction of PUSH (force) on charge


Ex 1) Direction?






Out of page




Force up






Force into page



Answer: Into or Out of the page?




Out of Page



Magnetic force is maximum
when charge moves
to field

(Charge shot up)



Magnetic force = 0
when charge moves ...


... parallel to field



Force on a charge

1. Fmag = Bqvsinq 

q is angle between
charge v and field

90 max, 0 degrees F = 0


B - flux density of magnetic field (strength) Teslas (T)


q - charge (C)


v - velocity (m/s)






Ex) Charge shot in field, speed and KE not changed. W=0 If perpendicular, charge will move in a circle


Bqv  = mv2/r



Bq  = mv/r



r  = mv/Bq



Page 259) Review Book #2 - #5





2) c


3) d


4) d


5) a


Handout p. 10) 36

Generator Principle



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Neodymium magnet/TV


School Block YouTube? Use file below.

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Warning: Doing this to your home TV
can permanently damage it!!



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