A copper wire of cross-sectional area =2.0 text mm2, resistivity =1.7× 10-8Ω m, carries a current of 1 A. The electric field in the copper wire is

Question

A copper wire of cross-sectional area =2.0 text mm2, resistivity =1.7× 10-8Ω m, carries a current of 1 A. The electric field in the copper wire is (A)  8.5× 10-5Vm-1  (B)  8.5× 10-4Vm-1  (C)  8.5× 10-3Vm-1  (D)  8.5× 10-2Vm-1

Tardigrade Admin · Accepted Answer

From symmetry considerations and also from theory (Va/Vd)=(Vb/Vc) E=(V/l)=(IR/l)=(Iρ l/Al)=(Iρ /A) =(1× 1.7× 10-8/2× 10-6) =8.5× 10-3Vm-1

Q. A copper wire of cross-sectional area $= 2.0 m m^{2},$ resistivity $= 1.7 \times 10^{- 8} Ω m,$ carries a current of 1 A. The electric field in the copper wire is

$8.5 \times 10^{- 5} V m^{- 1}$

$8.5 \times 10^{- 4} V m^{- 1}$

$8.5 \times 10^{- 3} V m^{- 1}$

$8.5 \times 10^{- 2} V m^{- 1}$

From symmetry considerations and also from theory $\frac{V _{a}}{V _{d}} = \frac{V _{b}}{V _{c}}$ $E = \frac{V}{l} = \frac{I R}{l} = \frac{I ρl}{A l} = \frac{I ρ}{A}$ $= \frac{1 \times 1.7 \times 10 ^{- 8}}{2 \times 10 ^{- 6}}$ $= 8.5 \times 10^{- 3} V m^{- 1}$

Q. A copper wire of cross-sectional area =2.0mm2, resistivity =1.7×10−8Ωm, carries a current of 1 A. The electric field in the copper wire is

8.5×10−5Vm−1

8.5×10−4Vm−1

8.5×10−3Vm−1

8.5×10−2Vm−1