## Electronic Communication Systems

Trade & Technology

## Quiz 2 :

Radio-Frequency Circuits

There is no difference in the behavior of a resistor at low and high frequencies. At all frequencies, resistor behaves same. Resistance of resistor depends on length, resistivity and area of the material used but not on the frequency applied. Therefore, there is no difference in the behavior of a resistor at low and high frequencies.

As the frequency increases, inductive reactance increases and capacitive reactance decreases. At some frequency, both the reactance is equal in magnitude and opposite in polarity. Hence, the total reactance becomes zero. Here, the circuit acts as a resonant circuit. This frequency at which both the reactance are equal is called self-resonance.

The components like resistor, capacitor and inductor are called lumped elements. These element values are constant in the circuit. These are called lumped constants. There is some capacitance, inductance and resistance present in the transmission lines itself and not visible. Every conductor has a finite resistance, if two lines are connected in parallel, there is some capacitance. Also, transmission line produces some electric field around it due to inductance. These all are called distributed constants. These lumped and distributed components affect the circuit differently at different frequencies. So, these two concepts are necessary.

There is no answer for this question

There is no answer for this question