Answer:
8.25 x 10^-3 V/m
Explanation:
Resistivity, ρ = 2.44 x 10^-8 Ohm m, Diameter = 1.8 mm
radius, r = 0.9 mm = 0.9 x 10^-3 m, l = 40 cm = 0.4 m, i = 860 mA = 0.86 A,
Let V be the potential difference and E be the electric field.
Use the formula for resistance
R = ρ l / A
R = (2.44 x 10^-8 x 0.4) / ( 3.14 x 0.9 x 0.9 x 10^-6)
R = 3.84 x 10^-3 ohm
According to Ohm's law
V = i x R
V = 0.860 x 3.84 x 10^-3 Volt = 3.3 x 10^-3 Volt
E = V / l = 3.3 x 10^-3 / 0.4 = 8.25 x 10^-3 V/m
