Question

Три электрические спирали соединены последовательно и включены в сеть с напряжением 220 В. Сопротивление первых двух спиралей равны соответственно 50 Ом и 10 Ом,а напряжение на их концах ровно 120В. Расчитайте силу тока в каждой спирали и сопротивление третьей спирали

Answer 1

50 Ом и 10 Ом,а напряжение на их концах ровно 120В
U=220 В   I - ?    R3-?
найдем общий ток
I = U12/(R1+R2)=120/(50+10)=2 А
Найдем полное сопротивление  R =U/I=220/2=110 Ом
R=R1+R2+R3
R3=110 -50-10=50 Ом - ответ

Answer 2

Calculation of Current and Resistance

To calculate the current and resistance in each spiral, we can use Ohm's Law, which states that the current flowing through a conductor is equal to the voltage across the conductor divided by its resistance.

Let's denote the resistance of the first spiral as R1 (50 Ω) and the resistance of the second spiral as R2 (10 Ω). The voltage across both spirals is given as 120 V.

Using Ohm's Law, we can calculate the current flowing through each spiral:

For the first spiral: I1 = V1 / R1, where I1 is the current flowing through the first spiral, V1 is the voltage across the first spiral (120 V), and R1 is the resistance of the first spiral (50 Ω).

For the second spiral: I2 = V2 / R2, where I2 is the current flowing through the second spiral, V2 is the voltage across the second spiral (120 V), and R2 is the resistance of the second spiral (10 Ω).

Let's calculate the values:

I1 = 120 V / 50 Ω = 2.4 A (ampere). I2 = 120 V / 10 Ω = 12 A (ampere).

Now, let's calculate the resistance of the third spiral.

Since the three spirals are connected in series, the total resistance of the circuit is the sum of the individual resistances:

R_total = R1 + R2 + R3, where R_total is the total resistance of the circuit, R1 is the resistance of the first spiral (50 Ω), R2 is the resistance of the second spiral (10 Ω), and R3 is the resistance of the third spiral.

We know that the total voltage across the circuit is 220 V Using Ohm's Law, we can calculate the total current flowing through the circuit:

I_total = V_total / R_total, where I_total is the total current flowing through the circuit, V_total is the total voltage across the circuit (220 V), and R_total is the total resistance of the circuit.

Since the current is the same in a series circuit, we can equate the total current to the sum of the currents flowing through each spiral:

I_total = I1 + I2 + I3, where I1 is the current flowing through the first spiral, I2 is the current flowing through the second spiral, and I3 is the current flowing through the third spiral.

Now, we can rearrange the equation to solve for R3:

R3 = V_total / I_total - R1 - R2.

Let's calculate the value of R3:

R3 = 220 V / (2.4 A + 12 A) - 50 Ω - 10 Ω = 220 V / 14.4 A - 60 Ω = 15.28 Ω.

Therefore, the current flowing through each spiral is 2.4 A for the first spiral and 12 A for the second spiral, and the resistance of the third spiral is 15.28 Ω.

Please note that the calculations assume an ideal circuit without any other factors affecting the resistance or current flow.