Question

ПОМОГИТЕ СРОЧНО!!!на железный проводник длиной 10 м и площадью поперечного сечения 2 мм^2 подано напряжение 12мВ. чему равно сила тока,протекающего по проводнику ?

Answer 1

po=0.13   L=10    S=2    U=0.012

I=U/R     R=po*L/S

I=U*S/(po*L)=0.006 A   (6 мА)

Answer 2

Calculation of Current

To calculate the current flowing through a conductor, we can use Ohm's Law, which states that the current (I) is equal to the voltage (V) divided by the resistance (R). In this case, the conductor is assumed to have negligible resistance, so we can use Ohm's Law directly.

Given: - Length of the conductor (L) = 10 m - Cross-sectional area of the conductor (A) = 2 mm^2 - Voltage (V) = 12 mV

To find the current (I), we need to determine the resistance (R) of the conductor. The resistance can be calculated using the formula:

R = ρ * (L / A)

Where: - ρ (rho) is the resistivity of the material (constant) - L is the length of the conductor - A is the cross-sectional area of the conductor

The resistivity of the material depends on the type of conductor being used. Since the type of conductor is not specified in the question, we cannot provide an exact value for the resistivity. However, we can proceed with the calculation using a typical value for copper, which is commonly used as a conductor.

For copper, the resistivity (ρ) is approximately 1.68 x 10^-8 Ω·m.

Using the given values and the formula for resistance, we can calculate the current:

R = (1.68 x 10^-8 Ω·m) * (10 m / (2 mm^2))

Converting the cross-sectional area from mm^2 to m^2: A = 2 mm^2 = 2 x 10^-6 m^2

Substituting the values into the formula: R = (1.68 x 10^-8 Ω·m) * (10 m / (2 x 10^-6 m^2))

Simplifying the expression: R = (1.68 x 10^-8 Ω·m) * (10 m / 2 x 10^-6 m^2) = 8.4 Ω

Now that we have the resistance, we can use Ohm's Law to calculate the current:

I = V / R = 12 mV / 8.4 Ω

Converting the voltage from millivolts to volts: V = 12 mV = 12 x 10^-3 V

Substituting the values into the formula: I = (12 x 10^-3 V) / 8.4 Ω

Calculating the current: I = 1.43 A

Therefore, the current flowing through the conductor is approximately 1.43 Amperes.

Please note that the resistivity value used in this calculation is an approximation for copper. The actual resistivity may vary depending on the material of the conductor.