PHY 114
Ohm’s Law
Abstract:
The purpose of this experiment was to find out the resistance of a resistor from a graph
that contained amps vs volts and to determine the value at which power is optimized. There were
three parts to this experiment, the first was setting the voltage which was determined to be
361+/- 0.05
. The second part was to find the resistivity of graphite and the diameter of the lead
Ω
rod was determined to be 0.22 +/- 0.05 cm, the slope of plotting R vs L was 234.3 +/- 12.19 Ω
/cm. The third and final part of this experiment was found by plotting P vs R(l) and the voltage at
optimization was 8.193V while the resistor at optimization was 85.40
.
Ω
Experimental Data:
Part 1A of this experiment was about finding the voltage with respect to amps of the
carbon resistor. First, the nominal value of the carbon resistor had to be
determined using the
color code, which was 361 +/- 0.05
. Next, fifteen voltages (0-15V) were ranged to produce a
Ω

graph that showed the relationship of voltage to amps. The slope was determined then used to
find the resistance. The resistance was then used to compare to the resistance estimated by using