1. The Project Dr. Len Trombetta 1 ECE 2100

2. The Goal Measure the internal resistance of a AA battery as it is drained of energy. Assume a model: an ideal voltage source in series with a resistance. Plot or chart the internal resistance as a function of…(whatever variable you think is appropriate). 2

3. Mechanics Experiment: Work with your lab partner – You will have the same data… – …but you will turn in separate reports Lab Notebook – All data and notes are recorded in the lab notebook – Your lab notebook will be separate from your lab partner’s notebook Report: A separate Formal Report will be submitted (discussed later…) 3

4. Materials and Tools 4 Batteries – Two different types, two batteries of each type (total #batteries = 4) Different brands Different chemical types … Equipment – You will need to purchase batteries and any other hardware you might want (battery holders, extra resistors …)

5. In Class You will begin thinking about several aspects of the project in class… – What about the model…? – What methods will we use? – How should we display the data? You will turn in a version of your Methods section after making some preliminary measurements. 5

6. For Next Week Purchase batteries (and anything else you might want). Start thinking about measurement methods. We will take a few measurements in class to see what the parameters are. 6

7. Technical Considerations Power dissipation in load resistors Effect of meter resistance Whether v batt is constant as the battery drains Plotting R int as a function of …? 7

8. Project Handout There are additional details in the project handout available on the class web site. You are responsible for all of these details. I strongly suggest you read it carefully. Otherwise, points will be lost… 8