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Discussion: In a RC circuit, the reactance of the capacitor was observed to decrease as expected when the frequency of the alternating current was increased. The capacitance of a capacitor was extracted from a plot of the reactance of the capacitor versus the frequency of the current within the circuit using the equation provided. This capacitance was found to be 1.025X10 -5F, while the expected capacitance was 1.08X10 -5F. This resulted in an experimental error of 5.1% which is within the acceptable error limits. This error may have been caused by errors which occurred throughout the experiment. In a RL circuit, the reactance of the inductor was observed to increase when the frequency of the alternating current was increased as expected. The inductance of the inductor was extracted from a plot of the reactance of the inductor versus the frequency of the alternating current within the circuit using the equation provided. This inductance was found to be 0.01H, while the expected inductance which was measured using a multimeter was 0.009H. This resulted in an experimental error of 11.1%, this error may have been caused by errors which occurred throughout the experiment. In a RCL circuit, the current within the circuit was observed to increase to a maximum point as the frequency of the alternating current was increased, after which, the current began to decrease as the frequency of the circuit was continually increased. The point at which the current reached its maximum value was extrapolated from the graph and noted as the resonance frequency (547.7Hz) of the circuit. The expected resonance frequency was then determined by recording the frequency at which the voltage across the inductor and capacitor were equal, this was found to be 537.0Hz. This resulted in an experimental error of 1.9% which is within the acceptable error limits. This error may have been caused by errors which occurred throughout the experiment. Errors which may have occurred throughout this experiment includes systematic errors associated with the instruments used along with slight fluctuations in frequency from the generator during readings. Gross errors such as incorrect extrapolation of the resonance frequency along with the rounding or misreading of values may have also contributed to the experimental errors which were observed.

Conclusion: The principles of alternating circuits were successfully investigated. The reactance of the capacitor was found to decrease as frequency was increased in an RC circuit. The reactance of the inductor was found to increase as frequency increased in RL circuits. The resonance frequency was also determined when the current reached its maximum in RLC circuits.

Questions: 1. What happens to the reactance of capacitor, reactance of inductor and the resistance of resistor when frequency increases to the infinity? From the equation for the resistance of the capacitor XC, as frequency increases to infinity XC will become zero. The resistance of the inductor X L is directly proportional to frequency and will also increase to infinity as frequency increases. The resistance of the resistor is independent of the frequency and will not be affected as the frequency increases.

2. What happens to the reactance of capacitor, reactance of inductor and the resistance of resistor when frequency approaches zero? The reactance of the capacitor XC is inversely proportional to frequency, therefore as frequency approaches zero XC increases. The reactance of the inductor is directly proportional to the frequency and will also approach zero as frequency approaches zero. The resistance of the resistor is independent of frequency and will not change as frequency approaches zero. 3. Does the resonance frequency of an AC circuit depend on the voltage delivered by generator? Explain your answer. 4. Does the resonance frequency depend on the magnitude of resistance R? Explain your answer. No. The resonance frequency is only dependent on the inductance of the inductor and the capacitance of the capacitor. f R =

1 2 π √ LC

5. What is special about the voltages on capacitor and inductor at the resonance frequency? At the resonance frequency the voltage across the capacitor and inductor are equal....