Solderless Breadbords, Open-circuits and Short-circuits

In this lab we analyze open and short circuits on a breadboard. We connect wires to the breadboard in various configurations and use a digital multimeter (DMM) to measure the resistance in each configuration. Using this information we determine whether we have an open circuit or a short circuit.

First, we connected the two wires in the same row. The DMM read 0.5 Ω,

Next we set the wires on the same row but on opposite sides of the central channel. The DMM reading was 2.21 MΩ.

Next, we set the wires on the same side of the central channel, but not on the same row or column. The reading on the DMM was 1.80 MΩ.

Finally, we connected two green wires on opposite sides of the central channel, but not on the same row. We used a third yellow wire whose ends were connected to the same row of each individual green wire. The reading on the DMM was 0.6 Ω.

After analyzing the data, we noticed that the first and last wiring configurations had very low resistances and the second and third wiring configurations had very high resistances. The low resistance configurations approached zero resistance while the high ones approached infinity. This suggests that the first and last configurations were closed circuits and the second and third configurations were open circuits.

This tells us valuable information about how the breadboard works:

• The two sections separated by the central channel are independent from one another.
• Anything plugged in to the same row on the same side of the central channel are connected together.
• A row on one side of the central channel can be connected to any row on the other central channel by connecting a wire that goes from one side to the other.