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Ohms Law for electric circuit
Ohm's law
The example is devoted to Ohm's law for an electric circuit in two versions: direct current and alternating current.
Task type:
Planeparallel problem of AC magnetics.
Geometry model:
Given:
Resistor R = 20 Ohm;
Inductance L = 0.02 H;
Current I = 1 A;
Frequency f = 0 Hz; 50 Hz.
Task:
Find the voltage drops across the circuit elements L, R and compare them with the analytical solutions
Solution
In Quickfield, an electrical circuit can be simulated in AC magnetics and in Transient magnetics modules. To simulate a DC current mode we use the transient problem with the timeconstant current source.
Analytical solution* for the direct current:
U(R) = I * R = 1 * 10 = 10 V.
U(L) = 0 V.
Analytical solution for the alternating current:
U(R) = I * R = 1 * 10 = 10 V.
U(L) = I * 2 * π * f* L = 1 * 2 * 3.14 * 50 * 0.02 = 6.28 V.
*Wikipedia: Ohm's law.
Result
Voltage drop calculated by Quickfield
DC
V(R) = 20 V, V(L) = 0 V

AC, 50 Hz
V(R) = 20 V, V(L) = 6.28 V

Download simulation files (files may be viewed using any QuickField Edition).