Experiment Description

Experiment

Experiment DL18    Phase Relationship


Objectives
  • Study the phase relationship between the applied voltage and the current in LR circuit, RC circuit and LRC circuit
  • Study how the phase relationship between the applied voltage and the current varies with frequency
  • Study the phase relationship between the applied voltage and the current in an LRC circuit during resonance
Description
In this activity, you will study the phase relationship between the output voltage and the current in LR, RC and LRC circuits. You will not only display the time-variations of V and I, but also the variation of V against I. If there is no phase difference between V and I, the later graph is a straight line.

In Experiment 1, an inductor is connected in series with a resistor across the power output of the Interface unit.

In Experiment 2, a capacitor is used instead of the inductor. You will also display the voltage across the capacitor, in addition to the output voltage and current.

In Experiment 3, the inductor, the capacitor and the resistor are connected in series across the power output of the Interface unit. By varying the frequency, you will study how the phase relationship varies accordingly.

Apparatus
Science Workshop 750 Interface [1]
Voltage sensor [1]
inductor (8.2 mH ) (or 240-turn coil) [1]
resistor (10 ohm) [1]
capacitor (100 mF) [1]
capacitor (330 mF) [1]
AC/DC Electronics Lab (alternative) [1]
Experiment