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Do magnetic forces obey Newton's third l...

Do magnetic forces obey Newton's third law. Verify for two current elements `dvecl_1=dlhati` located at the origin and `dvecl_2=dlhatj` located at (0, R, 0). Both carry current I.

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magnitude field due to current element `Idvecl_1` at a point on element `dvecl_2` , `vecB=(mu_0)/(4pi)(Idl)/(R^2)hatk`
Force on `dvecl_2` is, `vecF=IdlhatjxxB=Idlhatjxx(mu_0)/(4pi)(Idl)/(R^2)hatk`
`=(mu_0)/(4pi)(I^2dl^2)/(R^2)(hatjxxhatk)=(mu_0)/(4pi)(I^2dl^2)/(R^2)hati`
It can not be zero.
Force on `Idvecl_1` due to magnetic field by current `Idvecl_2` is zero as magnetic field of `Idvecl_2` has no interaction with current element `Idvecl_1`.
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