Grounding a Circuit - Electronics Lab Results

[StonieJ]

In a recent electronics lab, we designed a simple circuit consisting of only three resistors and a battery. After recording all the relevant data for the system (I, V drop, R, etc), we then grounded it by attaching a wire from one of the resistors to a metal bolt attached to a nearby water pipe. Doing so caused none of our values to change, which the TA said was expected. I'm assuming this is because the water pipe never fed back into the circuit meaning the loop wasn't complete (i.e. the wire from the circuit to the pipe was essentially "dangling" out from our circuit).

Basically, I just wanted to check to make sure this was a valid assumption.

 

[learningphysics]

In a recent electronics lab, we designed a simple circuit consisting of only three resistors and a battery. After recording all the relevant data for the system (I, V drop, R, etc), we then grounded it by attaching a wire from one of the resistors to a metal bolt attached to a nearby water pipe. Doing so caused none of our values to change, which the TA said was expected. I'm assuming this is because the water pipe never fed back into the circuit meaning the loop wasn't complete (i.e. the wire from the circuit to the pipe was essentially "dangling" out from our circuit).

Basically, I just wanted to check to make sure this was a valid assumption.

Yes, you're right.

 

[thepatientmental]

Yes, your assumption is correct. Grounding a circuit means providing a reference point for the circuit's voltage. In this case, the water pipe was not connected to the circuit in a way that would allow for the flow of current, so it did not affect the circuit's behavior. The wire from the circuit to the pipe was essentially acting as an open circuit, meaning there was no complete loop for the current to flow through. Therefore, the values for current, voltage, and resistance remained the same as if the circuit was not grounded. Overall, grounding a circuit is an important step in ensuring accurate measurements and proper functioning of the circuit, but in this particular case, it did not have any significant impact.