Lab Write up Model DC Circuits SimulationTo successfully write up a lab report, there are several things that you must accomplish.

1. Re-cap the procedure used to perform the experiment. This is a brief description of what you did during the experiment. (Stay away from using the first person form in this description.) The re-cap may be done section by section to simplify a multiple part experiment.

Example:The circuit in figure 1a was constructed on thebreadboard. A voltage (Es) of 5 Volts was applied and the resulting current was measured through R1 (Is), R2 (I1), and R3, and R4. (I2) Results are shown in Data Table 1.

Note the use of the circuit drawings in the write up. (it can be hand drawn neatly in pencil using a straight edge and a 0.5mm mechanical.) Also note that when a component or voltage or current is referred to, the corresponding component or voltage or current is named and shown in the figure drawn.

2. Show the data collected in tabular form. Data collected in an experiment should always be given in the precision taken (usually 2 places to the right of the decimal point in engineering notation is sufficient). Put data tables near the figure of the circuit, or draw it again so that the data can be compared to the circuit diagram. Always make sure the data table and the circuit diagram can be seen at the same time. If there are several circuits to be evaluated, put the data table immediately following the circuit diagram in the recap of the procedure.

Example:

Es Is (through R1) I1 (through R2) I2 (through R3) I2 (through R4)Value Predicted 5.00V 33.00mA 19.50mA 13.50mA 13.50mAValue measured 5.00V 34.26mA 20.44mA 13.82mA 13.82mA

Percent error 0% 3.82% 4.82% 2.37% 2.37%

Note that each reference to a circuit parameter is matched by a symbol or name on the circuit diagram. Also, note that the predicted values (pre-lab) are compared to the experimental values using a % error calculation. Whenever the word compare is used, use a % error calculation. This ensures the comparison has a standard numerical value .

3. Summarize the information you found when you performed the experiment in your own words. Use diagrams, and the circuit diagram. Remember, a picture is worth a thousand words. This section is generally the part of the write up that your manager will read first. It should contain observations and analysis illustrating what you did. Finally, offer a:

4. Conclusion. The conclusion can be the last few lines of the summary. It should answer the question: “How did this experiment meet the objectives?” The “How” in the question is specific. It is not correct to state that the experiment met the objectives without showing how this was done. If the summary was thorough, the conclusion can be quite short. Use experimental data in an example to show how the objective was met.

Example:In summary, this experiment demonstrated Ohm’s law and circuit equivalence.

The currents that were measured were predicted by using Ohm’s law. These predictions were then compared to measurements taken from the circuits that were built in lab. The measured values all had errors less than 5% when compared to the theoretical values. Circuit 1 and circuit 2 demonstrated Ohm’s law, and when the measurements from Circuit 2 were used in an Ohm’s law calculation, it demonstrated that Ohm’s law could be used to show the equivalence between the 2 circuits.

In conclusion, The stated objectives were met in this experiment in the comparison of theoretical and experimental data. Note that in Fig. 1a, the total resistance seen by the voltage source can be calculated by using Ohm’s law (Rt = 5.00V/34.26mA = 145.94). This agrees with the predicted value of 145.00 to an error of only 0.65%

Respectfully submitted,

Joe Student

The key to a successful write up is not verbosity, it is, instead, showing how the lab meets the stated objective in as concise a way as possible. Avoid giving the reader a lesson in theory. Assume his or her level is at least on par with yours. Use conversational language, as if you were describing the process to a fellow student, or co-worker. Don’t try to impress anyone with your writing skills, just get the point across in a short, and concise manner.

Tips:1. Keep it short, and to the point. Write informally, and clearly.2. Use circuit diagrams wherever possible to make your point.3. Make data tables neat and readable. Put them on the same page as your circuit.

diagrams.4. Make observations, then analyze the observations. Do this in the Summary.5. Answer the question “HOW did the lab meet the objectives” in the conclusion.6. Sign your work. Be proud of what you write.