The current density in a wire of radius a varies with radial distance r as J=(J_0r^2)/a, where J_0is a constant. Choose the incorrect statement.

The current density in a wire of radius a varies with radial distance

1.	The current density in a wire of radius a varies with radial distance r as J=(J_0r^2)/a, where J_0is a constant. Choose the incorrect statement.
Answer» Total CURRENT passing through the cross-section of the WIRE is`I=(piJ_0a^3)/2` Total current passing through the cross-section of the wire is`I=(3piJ_0a^3)/2` The field at a distance R gt a is `B=(mu_0J_0a^3)/(4r)` The field at a distance r gt a is `B=(mu_0J_0a^3)/(4A)` Answer :B

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The current density in a wire of radius a varies with radial distance r as J=(J_0r^2)/a, where J_0is a constant. Choose the incorrect statement.

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