Question

рассчитайте сопротивление следующих проводников изготовленных изиз никелиновой проволки длиной 400 см и площадью поперчного сечения 0.5 мм ^ 2 из константановой проволки длиной 50 см и площадью поперечного сечения 0.005 см ^ 22) сила тока в спирали электрической лампы 0.7 А. сопротивление лампы 310 Ом оприделите напряжение под которым находятся лампа Пожалуйста с обьяснением

Answer 1

1)R=pl/S=0,42Om*mm^2/m*4m/0,5mm^2=3,36Om

R=pl/S=0,5Om*mm^2/m*0,5m/0.5мм^2=0,5Om

2)I=U/R => U=IR=0.7 А*310Om=217B

Answer 2

Calculation of Resistance

To calculate the resistance of the given conductors, we can use Ohm's law, which states that resistance (R) is equal to the ratio of voltage (V) to current (I). The formula for resistance is:

R = V / I

Let's calculate the resistance for each conductor separately.

1. Nickel-chromium wire: - Length (L) = 400 cm = 4 m - Cross-sectional area (A) = 0.5 mm^2 = 0.00005 m^2 - Resistance (R) = V / I

2. Constantan wire: - Length (L) = 50 cm = 0.5 m - Cross-sectional area (A) = 0.005 cm^2 = 0.0000005 m^2 - Resistance (R) = V / I

Resistance of Nickel-Chromium Wire

To calculate the resistance of the nickel-chromium wire, we need to know the resistivity of the wire material. The resistivity (ρ) is a property of the material and is typically given in units of ohm-meter (Ω·m). The resistivity of nickel-chromium wire is approximately 1.10 x 10^-6 Ω·m [[1]].

Using the formula for resistance, we can calculate the resistance of the nickel-chromium wire:

R = (ρ * L) / A

Substituting the given values:

R = (1.10 x 10^-6 Ω·m * 4 m) / 0.00005 m^2

Calculating the resistance:

R ≈ 88 Ω

Therefore, the resistance of the nickel-chromium wire is approximately 88 Ω.

Resistance of Constantan Wire

To calculate the resistance of the constantan wire, we also need to know the resistivity of the wire material. The resistivity of constantan is approximately 4.9 x 10^-7 Ω·m [[2]].

Using the formula for resistance, we can calculate the resistance of the constantan wire:

R = (ρ * L) / A

Substituting the given values:

R = (4.9 x 10^-7 Ω·m * 0.5 m) / 0.0000005 m^2

Calculating the resistance:

R ≈ 490 Ω

Therefore, the resistance of the constantan wire is approximately 490 Ω.

Voltage across the Lamp

To determine the voltage across the lamp, we can use Ohm's law again. The formula for voltage is:

V = I * R

Substituting the given values:

V = 0.7 A * 310 Ω

Calculating the voltage:

V ≈ 217 V

Therefore, the voltage across the lamp is approximately 217 V.

In summary: - The resistance of the nickel-chromium wire is approximately 88 Ω. - The resistance of the constantan wire is approximately 490 Ω. - The voltage across the lamp is approximately 217 V.

Please note that these calculations are based on the given information and assumptions about the properties of the wires.