Sample%20report%20RLC - Copy (6)

Sample%20report%20RLC - Copy (6) - Experiment 5: Transients...

Info iconThis preview shows pages 1–4. Sign up to view the full content.

View Full Document Right Arrow Icon
Experiment 5: Transients and Oscillations in RLC circuits P. T. Debevec November 14, 2002 See Physics 301 Logbook #1, pages 113-117, data taken Sept 27, 2002. Purpose In this experiment we studied the transient and steady-state response of an RLC circuit. 1. In part A, we observed a damped oscillatory signal and measured the dependence of the period on the capacitance for fixed values of resistance and inductance. 2. In part B, we measured the dependence of the log decrement on resistance for fixed values of capacitance and inductance for a damped oscillatory signal. 3. In part C, we produced a critically damped signal and found the resistance for critical damping for a range of capacitances. 4. In part D, we measured the steady-state response of the RLC circuit to a sinusoidal input. We found the resonant frequency and bandwidth of the circuit. Equipment The equipment used in this experiment is described in the laboratory handout, E5_PTD_v4.pdf. I used Wavetek #943025, oscilloscope #943049, DMM #943033, decade capacitor box #2502, decade resistor box #48361, and inductor #6. Series resistance and inductance of inductor #6 The series resistance measured with the DMM was 14.46 . The DMM on the 100- scale has an accuracy of 0.010% of the reading plus 0.004% of the range, or 0.005 for this measurement. Lead resistance 1 and contact resistance are estimated to be of the order of 0.05 Ω. No measurement recorded below has greater than 1% accuracy. The series resistance of the inductor is then 14.5 ± 0.1 . The inductance measured with the Z-meter was 73.7mH. The calibration uncertainty of the Z-meter is not known. Part A: Period of damped oscillatory signals The circuit used for parts A, B, and C of the experiment is shown in Figure 1. 1 The hook-up wire in the 301 laboratory has a resistance of 0.0071Ω per foot.
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Figure 1. Circuit to study transient signals of RLC The circuit shows a fast-acting switch. In the upper position, the capacitor is charged by the battery to a voltage () 212 R RRV  +  . Both 1 R and 2 R are 10 , and V is 6 V. Thus the capacitor is charged to 3 V. In the lower position, the capacitor discharges through the variable resistor R and the inductor . Recall from above that the has a series resistance, L L L R , of 14.5 . The oscilloscope trigger is obtained from the voltage across 2 R . When the switch is thrown, the voltage across 2 R makes a transition from 3 V to 0 V in approximately 0.05 ms. This time is short compared to the oscillation period measured in part A. The oscilloscope is set to trigger on this transition, and the oscilloscope acquisition is set to single-shot mode. A typical oscilloscope trace is shown in Figure 2. Figure 2. Typical oscilloscope trace of a damped oscillatory signal
Background image of page 2
As expected, the initial voltage across the capacitor is 3 V. The period of the oscillation is obtained from this trace. For these data, 1.0 CF µ = and 0 R = 11 . The arrows indicate the first and eleventh zero crossing of the signal. This time difference, t 1 t , is equal to five periods.
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 4
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 11

Sample%20report%20RLC - Copy (6) - Experiment 5: Transients...

This preview shows document pages 1 - 4. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online