Day 11: Current Voltage and Resistance

Experiment #1

This experiment required an ammeter, a voltmeter, resistors, alligator wires and a power supply which we would use to record voltage and current data through a coiled conductor. We did six runs and plotted the data to illustrate their relationship:

The slope of the graph of our plotted data is linear, so the voltage,V, is directly proportional to the current, I, with a constant coefficient. The constant is the resistance, which means that the slope of an V vs I graph is magnitude of the resistor.

When two different resistors are used, the graph of their data produces two different slopes.

In the second experiment we will find out what factors that effect the magnitude of the resistor.

Experiment #2

The graph suggests that with a longer conductor the resistance increases. The linear graph suggests that the resistance is directly proportional to the length of the wire. 

In the graph, the red data point is the the resistance of a copper conductor. It is clearly not similar to our other data. Since this is a different material, we can infer that different materials also affect the resistance.

Therefore, we conclude that the magnitude of the resistance depends on the length, material, and the cross sectional area.