rlc circuit
Measurements of Capacitance and Inductance
Purpose: To use equipment and techniques to determine the structure of a hidden series RLC circuit and to measure the values of the various components in that circuit.
Theory:
To see how an RLC circuit works, consider the circuit in Figure 1 with the capacitor initially charged.
Fig. 1 RLC Circuit
Since there is a conducting wire connecting the negative side of the capacitor to the positive, a current will begin to flow in the counterclockwise direction. As it does, several things happen. The first is that the resistor will begin to strip energy from the current and convert it to thermal energy. The second is that the current through the inductor will result in a magnetic field. However, since the current is transient (not constant), the magnetic flux through the inductor is not constant, resulting in an emf across the inductor, pointing in the opposite direction of the voltage across the capacitor.
Once the capacitor is discharged, the emf in the inductor, in trying to prevent the change in magnetic flux, will result in a current in the opposite direction. This causes an opposite charge to start building up on the capacitor. The negative charge will be on the upper plate. This transient current will continue to flow until the capacitor is charges and the magnetic flux through the inductor becomes zero. At this point, the capacitor current starts discharging and the current flowing in the clockwise direction.
This process would continue forever if it were not for the resistor. Each time the current flows through the resistor, some of the electrical energy changes into thermal energy. Eventually, all of the electrical energy changes into thermal energy and the charges will stop from flowing.
Data:
Part I:
Circuit board #: 3
Resistance: 23.2
Inductor: 71.1
Capacitance: infinity
Diagram of circuit in series:
Part II:
Inductor:
Purpose: To use equipment and techniques to determine the structure of a hidden series RLC circuit and to measure the values of the various components in that circuit.
Theory:
To see how an RLC circuit works, consider the circuit in Figure 1 with the capacitor initially charged.
Fig. 1 RLC Circuit
Since there is a conducting wire connecting the negative side of the capacitor to the positive, a current will begin to flow in the counterclockwise direction. As it does, several things happen. The first is that the resistor will begin to strip energy from the current and convert it to thermal energy. The second is that the current through the inductor will result in a magnetic field. However, since the current is transient (not constant), the magnetic flux through the inductor is not constant, resulting in an emf across the inductor, pointing in the opposite direction of the voltage across the capacitor.
Once the capacitor is discharged, the emf in the inductor, in trying to prevent the change in magnetic flux, will result in a current in the opposite direction. This causes an opposite charge to start building up on the capacitor. The negative charge will be on the upper plate. This transient current will continue to flow until the capacitor is charges and the magnetic flux through the inductor becomes zero. At this point, the capacitor current starts discharging and the current flowing in the clockwise direction.
This process would continue forever if it were not for the resistor. Each time the current flows through the resistor, some of the electrical energy changes into thermal energy. Eventually, all of the electrical energy changes into thermal energy and the charges will stop from flowing.
Data:
Part I:
Circuit board #: 3
Resistance: 23.2
Inductor: 71.1
Capacitance: infinity
Diagram of circuit in series:
Part II:
Inductor: