What is a pure resistance circuit and how to distinguish it? 2

2. Phase relationship

In a pure resistance circuit, due to the absence of inductance and capacitance, the phase difference between current and voltage is always zero. This means that they will reach both peak and zero values simultaneously. This can be verified by observing the waveforms of current and voltage in the circuit through an oscilloscope.diode

3. Frequency characteristics  diode

Pure resistance circuits are insensitive to frequency. Unlike circuits containing inductors or capacitors, whose impedance varies with frequency, the resistance value in pure resistance circuits remains constant at any frequency. Therefore, regardless of how the frequency of the input signal changes, the performance of the circuit (such as the magnitude of the current) will not change due to changes in frequency.diode

4. Power factor

In a pure resistance circuit, the power factor (PF) is always 1. Power factor is defined as the ratio of active power to apparent power, and in a pure resistance circuit, because the voltage and current phases are the same, all input electrical energy is converted into thermal energy on the resistance, without the generation of reactive power.diode