ECEN 2250
Circuits/Electronics 2
Spring 2008
24/01/2008
Lab Worksheet: Lab 2
Note: This worksheet is based on an earlier version authored by P. Mathys and modified by Lucas Portelli and Garret Moddel
NAME :_________________________________
Lab Section:_______
Q1. What values did you get for V and I in E1? What was the resistance
measured with the ohmmeter? Attach the I-V graph and the data you
consider necessary. Discuss any deviations you see from Ohm’s law.
Discuss how you estimated the resistor’s value and discuss any
discrepancies between your estimated value and the value measured with
the ohmmeter.
Q2. Attach a labeled Matlab graph of the i-v characteristic of the pencil that
you measured in E1. What value(s) did you obtain for the resistance of the
pencil? Is the pencil (approximately) a linear device? If not, does the
resistance increase or decrease as i increases? What was the maximum
power that the pencil had to dissipate during your i-v measurements?Does
the resistance increase, decrease, or stay constant as the pencil gets more
hot?
Q3. What color LED did you use in E3? Attach a labeled Matlab plot that
shows the (v, i) pairs that you measured and also the interpolation between
those points. What model do you propose for this data set? Explain and
diagram what you think necessary.