A copper wire of length 10 m and radius $(10 ^{- 2} /\sqrt\pi )$ m has electrical resistance of 10 Ω. The current density in the wire for an electric field strength of 10 (V / m) is :

(1) 10^{ - 5 }A/m^{2}

(2) 10^{ }^{5 }A/m^{2}

(3) 10^{ 4 }A/m^{2}

(4) 10^{ 6 }A/m^{2}