Hall effect/Force on a current carrying wire

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The discussion centers on a homework problem involving a conducting rectangular solid moving through a magnetic field and the resulting electric field and potential difference. Key equations related to electric and magnetic forces are referenced, emphasizing the Hall effect's principle where electrons accumulate on one side of the block due to the magnetic force. Participants highlight the necessity of knowing the block's velocity to solve the problem accurately, as it affects the calculations for electric field (E) and potential difference (V). There is a consensus that the velocity information appears to be missing from the question, which is essential for deriving the correct answers. The conversation concludes with an acknowledgment that the problem cannot be solved without this critical detail.
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Homework Statement


A conducting rectangular solid of dimensions
dx=5m
dy=3m
dz=2m
moves at a constant velocity through a uniform magnetic field B=(30mT)j. What are the resulting a)electric field within the solid,in unit vector notation?
b)potential difference across the solid?
20170709_222420-1.jpg

Homework Equations


●Electric Force=qE
●Magnetic Force=Bqv
●E=V/d
●Basic theory of Hall effect:On applying a magnetic field perpendicular to the block,some electrons get accumulated at one side of the block due to the magnetic force acting on them,which after a while causes an electric field to be produced inside the block across it's width ,which opposes and finally cancels the effect of the magnetic field.

The Attempt at a Solution


I think the velocity ought to be mentioned in the question.
It just says constant velocity.That could mean the block is moving either across the x-axis or along z axis. (Only then will Hall effect be observed and an electric field and hence potential difference will be observed)

Then,we can just equate electric and magnetic force (equations meantioned above)
And first find out E,then through the 3rd formula V.
However,I find out both E and V in terms of v,
to see if both the answers correspond to the same v as they should,and the answers matching(for a velocity of -200i,but we are not supposed to do that :p)
So,in a nutshell:Can I do this question without knowing the velocity before-hand??
 
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Tanishq Nandan said:
So,in a nutshell:Can I do this question without knowing the velocity before-hand??
You are right, you need to know the velocity. I suspect that the velocity was meant to be given but was inadvertently left out.
 
Ok,thanks
 
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