chapter 1 correction

great site, will refer it to my son to learn from.

found an error in the text vol 1 - dc ohms law
http://www.allaboutcircuits.com/vol_1/chpt_2/7.html

It also means that voltage measurements between sets of "electrically common" points will be the same. That is, the voltage between points 1 and 4 (directly across the battery) will be the same as the voltage between points 2 and 3 (directly across the resistor). Take a close look at the following circuit, and try to determine which points are common to each other:

should read, perhaps.

It also means that voltage measurements between sets of "electrically common" points will be the same. That is, the voltage between points 1 and 4 (directly across the battery) will be the same as the voltage between points "4" and 3 (directly across the resistor). Take a close look at the following circuit, and try to determine which points are common to each other:

no biggie as the text is very descriptive, just a typo

This is the schematic you are referring to:



I think the original paragraph is correctly describing what it means.

It also means that voltage measurements between sets of "electrically common" points will be the same. That is, the voltage between points 1 and 4 (directly across the battery) will be the same as the voltage between points 2 and 3 (directly across the resistor). Take a close look at the following circuit, and try to determine which points are common to each other:

Click to expand...

as opposed to your correction:

It also means that voltage measurements between sets of "electrically common" points will be the same. That is, the voltage between points 1 and 4 (directly across the battery) will be the same as the voltage between points "4" and 3 (directly across the resistor). Take a close look at the following circuit, and try to determine which points are common to each other:

Click to expand...

As stated, points 1 and 4 are across the battery, while 4 and 3 are the wire, not the resistor. Point 1=2, 4=3. Points 1 and 4 measure 10V, points 2 and 3 also measure 10V.

I suspect you are referring to the wrong illustration for this paragraph.

I do not believe there is an error. It could use some clarification though, as in referring to the image by name instead of assuming the reader knows which illustration it is referring to. Since there are no designations on the images they would have to be added to correct this.

The text is correct as is.

The main problem I have with this page is that it talks about voltage "between" points. This would have been a good place to explain to people that voltage is relative and has a directrion (1 to 4 is 10V and 4 to 1 is -10V)

If anyone wants to draft an addition/clarification to the page in question, please post here.