TA’s name
Partner’s name
Introduction
In this lab, we learned about the oscilloscope that was helpful in introducing ideas related to AC Signals. An Oscilloscope is an instrument that converts electronic and electrical signals to a visual display, as two dimensional graph of one or more electrical potential. In relation to AC signals, its properties of linear circuits can be examined by a sinusoidal waveform recorded in the generator. The computer was used a generator to bring out the AC signals. A 1kΩ resistor was connected to the function generator. The Oscilloscope had to be connected to the resistor and the volts/division was recorded after using the auto scale option.
Time/div settings were also measured at after doing the same. The Vp, Vpp and frequency were calculated. Frequency was calculated by finding the period T then finding it’s reciprocal sinceF=1/T. The frequency would be later changed to 2 to repeat some procedures. The percent difference between the calculated and measured values of frequency and Vpp was done. The percentage difference in frequency was considerable smaller to attest that the experimental results were not far off from the theoretical data. The Vpp’s however, was minimal hence concluding the result was indeed closer to the theoretical data.
Tabulated below are the values for Vp, Vpp, and frequency from measuring time/div & volt/div settings and the cursors including the percent difference between the measured and calculated values.
Calculations
When using 1kHz Period, T was calculated and since, F=1/T it would be helpful.
T=timediv×voltsdiv
=100 µs ×1.00 V
= 100 ×10-5s
Hence, F=1/T
= 1/100 ×10-5s
=1000 Hz
Vpp =2.33 V Vp =4.66 V
When 2 kHz was used, Period, T was calculated to help find the frequency since, F=1/T
T=timediv×voltsdiv
=200µs ×1.00 V
= 200 ×10-5s
Hence, F=1/T
= 1/200 ×10-5s
=2000 Hz
% calculations involving; Vp, Vpp, and frequency are as follows;
Vp, △V=2.33-2.312=0.018 V
% Diff=0.0184.642×100=0.338
Vpp, △V=4.66-4.624=0.036 V
% Diff=0.0369.284×100=0.338
Frequency, △F=2000-1000=0.036 V
% Diff=10003000×100=33.33
Questions
When using the generator set at 1 kHz, the values of volts/div and the time/div settings after using auto scale were found to be,
VoltsDiv=1.00V, TimeDiv=200µs
After adjusting the time/division setting so that only one cycle was displayed on the screen, the new time/division setting was found to be, TimeDiv=200µs
Through the toggle button, time for making one oscillation was found to be, △t= 1000 µs, and measured voltage, the Vp was found to be, 2.312V while Vpp was, 4.624V.
Frequency at 2 kHz, the new time/division setting was found to be, TimeDiv=200µs
Through the toggle button, Period T was, △t= 500 µs, and measured voltage, Vp was found to be, 2.33V while Vpp was, 4.66V.
The difference in percentage results from the alternation of frequency that affects the output.
When the time/div is small, the signal remains constant but when it is increased, the signal vibrates.
Error/Conclusion
Since the percent error wasn’t zero, there must have been some error involved .I may have resulted from, the resistance in the wires connecting the components and the loose knobs of the Oscilloscope. During the calculations, the resistance was factored out. Therefore Oscilloscope can be used to measure the p.d and time interval and are displayed in form of waveforms on the screen. Hence this theory can be adapted in introduction to AC signals.
