wat was the answer to that beaker question with the wires in it?? (1 Viewer)

iH

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I used F/l = (k.I1.I2)/d

where d = distance between wires
i = current
l = length of interaction (above the solution - i think it was 0.35m?)

using the right hand rule.... the wires carry a circular magnetic field which CANCELS between the wires....due to a decrease in magnetic flux between the wires, they pull in towards each other...

if they were going the same way, the magnetic flux density between the wires is greater and pushes the wires away.
 

~TeLEpAtHeTiC~

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what i wann ask u ppl is..did u all use the right units... huh huh ...yeah thats right
u might hav done it right..but did u use right units..
ie 1.5cm --> 0.0015m and 0.35 m --> well...0.35 :p

just checking..cause i was talking bout it to my mate..and he goes...that question was so easy.. and i was like did u convert the units..and he went..wah?..
poor kid lol
 

walla

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iH that's incredibly wrong
figure out the direction of the field one wire is exerting on the other
then think of a moving charge in that field
same direction = attraction
 

~TeLEpAtHeTiC~

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no silly, becuase there is conducting material in the beaker it acts out a circiut, becuase of that in any circiut there is no way there can be attraction within the two wires becuase the cureent is always flowing in opposite directions (generally)
sorry mate
 

iH

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Originally posted by ~TeLEpAtHeTiC~
no silly, becuase there is conducting material in the beaker it acts out a circiut, becuase of that in any circiut there is no way there can be attraction within the two wires becuase the cureent is always flowing in opposite directions (generally)
sorry mate
exactly. they flow in opposite ways.

remember the OTHER right hand rule? the thumb goes in direction of current, your fingers curl around in the direction of the magnetic field.

chuck those two together (when they go opposite ways) and magnetic flux is cancelled....it's attraction.
 
N

ND

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Originally posted by iH
exactly. they flow in opposite ways.

remember the OTHER right hand rule? the thumb goes in direction of current, your fingers curl around in the direction of the magnetic field.

chuck those two together (when they go opposite ways) and magnetic flux is cancelled....it's attraction.
Nah it doesn't work like that, they attract when the current is travelling in the same direction.
 
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ND

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Originally posted by ~TeLEpAtHeTiC~

u might hav done it right..but did u use right units..
ie 1.5cm --> 0.0015m and 0.35 m --> well...0.35 :p
1.5cm --> 0.015m.
 

walla

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sorry iH, currents in different directions repel
 

~TeLEpAtHeTiC~

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Originally posted by iH
exactly. they flow in opposite ways.

remember the OTHER right hand rule? the thumb goes in direction of current, your fingers curl around in the direction of the magnetic field.

chuck those two together (when they go opposite ways) and magnetic flux is cancelled....it's attraction.
Originally posted by ND
Nah it doesn't work like that, they attract when the current is travelling in the same direction.
repel opposite direction
attract same direction

Originally posted by ND
1.5cm --> 0.015m.

lol sorry..typo.. beter not hav made that mistake in exam :S
 

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Originally posted by Bannanafish
heheeh it's funny doing the right hand rule in the exam hall :p
you know this one guy in my class asked (in all seriousness) whether we would be allowed to take a fake right hand into the exam with us
 

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