You'll enter your results for this exercise in the WebAssign assessment V119. Begin by watching the clip, Potential Difference, Current, and Power in Cooking a Hot Dog:  Streamed / RealPlayer / Flash. Note that in the WebAssign assessment there will also be two end-of-chapter questions (10 and 12) related to the subject of resistance and resistivity. As something extra, here's a video clip (mpeg) showing what happens when the hot dog is replaced with a pickle.

You'll record data in WebAssign in a table like the one below. While the teacher calls out the voltage and current every 15 s, you should take data at finer time intervals of 10 s. Just open the video to full screen. It's clear enough to read the meters.This will also be more accurate than the teacher's numbers, because he was trying (unsuccessfully) to read both meters simultaneously.

Elapsed time (s)	Voltage (V)	Current (A)	Average Current (A)	Thermal energy deposited during time interval (J)
0	<_>	<_>
10	<_>	<_>	<_>	<_>
20	<_>	<_>	<_>	<_>
30	<_>	<_>	<_>	<_>
40	<_>	<_>	<_>	<_>
50	<_>	<_>	<_>	<_>
60	<_>	<_>	<_>	<_>
70	<_>	<_>	<_>	<_>
80	<_>	<_>	<_>	<_>
90	<_>	<_>	<_>	<_>

The following information isn't repeated in the WebAssign form, so take note of it here. You're to calculate the total amount of thermal energy deposited in the hot dog while it was cooking (from the time that the electricity was turned on until the current dropped almost to 0). Here's an approximate technique that will be sufficiently accurate:

1. In order to account approximately for the change in current with time, calculate the average current for each time interval and record in the table. This is simply the average of the current at the present elapsed time and the immediately previous elapsed time. For example, the average current that you would enter for an elapsed time of 40 would the the average of the currents at 30 and 40 s.

2. Calculate the thermal energy deposited in the hot dog during each time interval as the product of the Voltage, Average Current, and time interval. Note this is the time interval rather than the Elapsed Time.

3. Add the numbers in the energy column to get the total thermal energy deposited.