PHY222, Elements of Physics II
Joule Equivalent of Electrical Energy, 22 February 2008

Theory Requirements:

1. Review power in electric circuits.
2. State the expected relationship between electric quantities and thermal quantities.
3. State the expected value of the J conversion factor, and identify how the main quantity measured in the experiment determines J.

Comments on the Procedure:
The procedure is given in the lab manual. In your write-up, SUMMARIZE the major techniques in the measurements. Identify as usual what you are measuring (and how), and what elements you are controlling. DO NOT clone the lab manual (or other sources) - read the procedure, digest it, summarize it concisely.
For anyone who has not yet used Data Studio, some of the procedure relating to the program can be difficult to visualize. I plan to post screenshots of important windows some time Tuesday afternoon. When writing this part of the procedure, detailed descriptions of using the computer are NOT necessary, but do identify the key parameters you will be inputting into the program.
It would also be a good idea to list anywhere you identify as a potential problem or question that could come up during the experiment. This is certainly optional, but if, as you read the procedure, there is a step that doesn't make sense yet, go ahead and say so in the write-up.

Pictures and Procedure CORRECTIONS:
For step 3 of Data Acquisition Setup: During the discussion of the Sensors menu, we are only concerned with a Temperature Sensor. Where it says "Voltage Sensor" is WRONG. DO NOT add a voltage sensor.
Picture
Data Acquisition, Step 5: Picture
Data Acquisition, Step 7: Picture

Results Checklist:

• Report a, the slope of the regression line found in Data Studio, ALONG with its associated uncertainty (also given by Data Studio).
• Report your values for J and the associated percent error, compared with the true value.
• There is a formula that relates the statistical uncertainty in a to that of the J value:
  
• Show a sample calculation, for your calculations of J and for the uncertainty in J.

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