Question

1. Проводник сделан из меди, имеет длину 100см и площадь поперечного сечения 3,4 мм? Проводник включен в цепь постоянного тока напряжением 0,2 В. Найдите силу тока. (Удельное сопротивление определите по таблице). [4]​

Answer 1

Ответ:

см.на фото...............

Answer 2

Calculation of Current

To find the current flowing through the conductor, we need to 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 resistance is determined by the specific resistance (or resistivity) of the material and the dimensions of the conductor.

The formula for resistance is:

R = (ρ * L) / A

Where: - R is the resistance - ρ (rho) is the specific resistance or resistivity of the material - L is the length of the conductor - A is the cross-sectional area of the conductor

In this case, the conductor is made of copper, which has a specific resistance of approximately 0.0000017 ohm-meter (Ω·m).

Given: - Length of the conductor (L) = 100 cm = 1 meter - Cross-sectional area (A) = 3.4 mm² = 0.0000034 m² - Voltage (V) = 0.2 V

Using the formula for resistance, we can calculate the resistance of the conductor:

R = (0.0000017 Ω·m * 1 m) / 0.0000034 m²

Simplifying the equation:

R = 0.5 Ω

Now, we can use Ohm's Law to find the current (I):

I = V / R

Substituting the given values:

I = 0.2 V / 0.5 Ω

Simplifying the equation:

I = 0.4 A

Therefore, the current flowing through the conductor is 0.4 Amperes.

Specific Resistance of Copper

The specific resistance (or resistivity) of copper is approximately 0.0000017 ohm-meter (Ω·m) This value represents the resistance of a 1-meter long copper wire with a cross-sectional area of 1 square meter.