Find magnetic force on a squar loop

leonne
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Homework Statement


suppose that mag field is B=kz \stackrel{^}{x}
find force on a square loop(side a) lying in the yz plane and centers at origin, if it carries a current I flowing counter clock whne u look down x axis

Homework Equations


Fmag=I\int(dl x B)


The Attempt at a Solution


Why does The force on the left side (toward
the left) cancels the force on the right side (toward the right)? Also than the answer is
netforce= 2(IaB)=2(Ia(ka/2)=Ia2k up

How did B turn into ka/2? and where did the "a" come from?
 
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hi leonne! :smile:

(have an integral: ∫ and try using the X2 icon just above the Reply box :wink:)
leonne said:
suppose that mag field is B=kz \stackrel{^}{x}
find force on a square loop(side a) lying in the yz plane and centers at origin, if it carries a current I flowing counter clock whne u look down x axis

Homework Equations


Fmag=I\int(dl x B)

…the answer is
netforce= 2(IaB)=2(Ia(ka/2)=Ia2k up

How did B turn into ka/2? and where did the "a" come from?

(do you mean B = kzx ? :confused:)

B is kz along the lines z = ±a/2, so B = ±ka/2 :wink:
 
hmm tried to make it B=kz x^ (x hat)
o ok thxs hmm
 
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