Answer:
The phase angle between the generator voltage and the resistor voltage in an AC circuit is determined by the relationship between the voltage and the current, as described by Ohm's Law.
At low frequencies, the resistor behaves as a purely resistive element, meaning that the current flowing through it is in phase with the voltage across it. Therefore, the phase angle between the generator voltage and the resistor voltage is 0 degrees.
However, as the frequency of the AC signal increases, the impedance of the resistor becomes more complex, with both resistive and reactive components. The reactive component of the resistor's impedance is proportional to the frequency of the signal, so as the frequency increases, the reactive component becomes more significant.
This reactive component causes the current to lead or lag the voltage, depending on the sign of the reactance. In the case of a purely resistive element, the current leads the voltage by 90 degrees. As the frequency increases, the current leads the voltage by a smaller angle because the reactive component of the resistor's impedance becomes less significant at higher frequencies.
Therefore, the phase angle between the generator voltage and the resistor voltage decreases as the frequency is increased, approaching 0 degrees as the frequency becomes very high.