Mag field in a current carrying square

[cupid.callin]

Homework Statement

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The Attempt at a Solution

answer says that its 0
I am guessing there is some problem in question ... the field won't be 0 at center .. it can't be ... field due to AB and CD gets canceled but field of AD and BC is in same direction and won't get canceled ...

 

[saubhik]

magnetic field due to AD and BC are getting cancelled, assuming both paths ADC and ABC have same resistances for currents in both paths to be same.
magnetic field due to ABC is upward and due to ADC is downward at the centre.

 

[cupid.callin]

i guess you are getting the question wrong ...

the figure is from what the question says "previous question" ... its not exactly of the question i gave ...