Vol I - DC, Chapter 5, Page 2:
http://www.allaboutcircuits.com/vol_1/chpt_5/2.html
The diagram:
http://sub.allaboutcircuits.com/images/00090.png
The diagram is introduced with, "[...] we can go back to our original circuit schematic and note the current through each component:"
Possibly deliberately omitted for visual simplicity, but only two of the three resistors actually have their current noted in the diagram. R2 is labeled with its resistance and an arrow for current flow, but not the "I = 500 uA" found next to R1 and R3.
http://www.allaboutcircuits.com/vol_1/chpt_5/2.html
The diagram:
http://sub.allaboutcircuits.com/images/00090.png
The diagram is introduced with, "[...] we can go back to our original circuit schematic and note the current through each component:"
Possibly deliberately omitted for visual simplicity, but only two of the three resistors actually have their current noted in the diagram. R2 is labeled with its resistance and an arrow for current flow, but not the "I = 500 uA" found next to R1 and R3.