The Lab Policy is here just to remind you of your responsibilities.
Lab meets in room 3250 SEL. Be sure to find that room BEFORE your first lab meeting. You don't want to be late for your first (or any) lab session do you? Arrive on time for all lab sessions.
You must attend the lab section in which you are registered. You can not make up a missed lab session! So, be sure to attend each lab session.
REMEMBER: You must get a score of 65% or greater to pass lab. And, you must pass lab to pass the course.
It is very important that you prepare in advance for every experiment. The Title page and the first four parts of your report (Purpose, Theory, Circuit Analysis, and Procedure) should be written up BEFORE you arrive to your lab session. You should also prepare data tables and bring graph paper when necessary. To insure that you get into the habit of doing the above, your lab instructor will be collecting your preliminary work at the beginning of your lab session. Up to four points will be deducted if this work is not prepared or is prepared poorly. This work will be returned to you while you are setting up the experiment.
NOTE: No report writing (other than data recording) will be allowed until after you have completed the experiment. This will insure that you will have enough time to complete the experiment. If your preliminary work has also been done then you should easily finish your report before the lab session ends. Lab reports must be submitted by the end of the lab session. (DEFINE END OF LAB SESSION = XX:50, where XX:50 is the time your lab session officially ends according to the UIC TIMETABLE.) If your report is not complete then you must submit your incomplete report. If you prepare in advance you should always have enough time to complete your experiment and report by the end of the lab session.
End Lab Policy
Be sure to print a copy of experiment #2 and bring it with you to your lab session. There will not be any copies available in the lab.
Occasionally I will be making some changes to the procedures of an experiment. However, this week you will be doing experiment #2 exactly as is.
The purpose of this experiment is to get some practice measuring voltage using the oscilloscope. You will be practicing direct and differential measuring techniques. You will also learn that under certain conditions the scope can give what appears to be wrong values if connected to the circuit incorrectly.
You will also learn how to construct a circuit on the "breadboard" and how to set the DC and AC power supplies.
Your circuit analysis will lead you to the expected values of the various voltages indicated in the circuit diagram. You will then measure the voltages and compare that data to your calculated values from your circuit analysis. (i.e. do some error analysis)
To find a voltage in this circuit first use Ohm's law to find the total current. Then find the individual voltages using Ohm's law again.
So,
| I = | Vs/(R1 + R2 + R3) |
| V1 = | I*R1 |
| V2 = | I*R2 |
| V3 = | I*R3 |
| V4 = | I*(R1 + R2) |
| V5 = | I*(R2 + R3) |
Note if Vs is a pure DC voltage then all of the above voltages will also be pure DC (i.e. constant values.) If Vs is an AC voltage then all of the voltages will also be AC.
DC + AC Example (NOTE: THESE ARE NOT THE VALUES FROM THE EXPERIMENT)
| I = | (10 + 25sin(100t))/(10K + 15K + 25K) |
| = | 0.2 + 0.5sin(100t) mA. |
| So, | |
| V2 = | 0.2 + 0.5sin(100t) mA.*15K |
| = | 3 + 7.5sin(100t) volts |
Hope this helps you with your preparation for experiment #2.