A copper wire of cross-sectional area 2.0 mm 2 resistivity =1.7 × 10-8 Ω, carries a current of 1 A. The electric field in the copper wire is

Question

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

Tardigrade Admin · Accepted Answer

E=(V/l)=(i R/l)=(i ρ l/A l)=(i ρ/A)=(1 × 1.7 × 10-8/2 × 10-6) =8.5 × 10-3 Vm -1

Q. A copper wire of cross-sectional area $2.0 m m^{2}$ resistivity $= 1.7 \times 1 0^{- 8} Ω$ , carries a current of $1 A$ . The electric field in the copper wire is

$8.5 \times 1 0^{- 5} V m^{- 1}$

$8.5 \times 1 0^{- 4} V m^{- 1}$

$8.5 \times 1 0^{- 3} V m^{- 1}$

$8.5 \times 1 0^{- 2} V m^{- 1}$

$E = \frac{V}{l} = \frac{i R}{l} = \frac{i ρl}{A l} = \frac{i ρ}{A} = \frac{1 \times 1.7 \times 1 0 ^{- 8}}{2 \times 1 0 ^{- 6}}$
$= 8.5 \times 1 0^{- 3} V m^{- 1}$

Q. A copper wire of cross-sectional area 2.0mm2 resistivity =1.7×10−8Ω, carries a current of 1A. 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