General DC Circuit: Voltage drop different from supply source

[sugz]

Sorry to be picky but...

The resistor tolerance doesn't explain an apparent breech of KVL. It only makes the calculated voltages different from the actual voltages.

Hi, I am aware of this but to my knowledge, I do not know what breeched the KVL rule. Any ideas of what I could have done incorrectly?

 

[NascentOxygen]

Hi, I am aware of this but to my knowledge, I do not know what breeched the KVL rule. Any ideas of what I could have done incorrectly?

You've done nothing incorrectly. If the resistor values are not exactly equal to their nominal value, the sum of the resistor voltages must still exactly equal the power supply voltage. It can't be less, and it can't be greater. The individual resistor voltages may differ owing to value tolerances, but their sum remains the same.

 

[sugz]

In that case, is it safe to say that the experiment was done correctly even though the power supply voltage was different than the sum of the resistor voltage by about 0.8% percent. In addition, is this expected when performing a lab as such? This is my first circuits lab and so I was confused. If you can clear up this for me, I would really appreciate it!

 

[CWatters]

Yes experiment seems fine. The only thing I would have done differently is to check the bench supply voltage using the same meter you used to measure the voltages on the resistors.

 

[NascentOxygen]

In that case, is it safe to say that the experiment was done correctly even though the power supply voltage was different than the sum of the resistor voltage by about 0.8% percent. In addition, is this expected when performing a lab as such? This is my first circuits lab and so I was confused. If you can clear up this for me, I would really appreciate it!

To get measurements to agree within 0.8% is outstanding!! Congratulations! :)

Experiment measurements in later lab classes will probably never be in such close agreement. You'll just have to get used to it! :w