Continuing the coverage of the Arduino platform with some electronics revisions, an introduction to some communication issues, and some pointers about datasheets. Part of the Interactive Media Master's program at the University of Limerick.
5. Kirchhoff’s Laws
first law / current law
The current flowing through a given circuit
point is equal to the sum of the currents
flowing into that point and is equal to the
sum of currents flowing out of that point.
Resistors in series - RTOTAL = R1 + R2
VOUT = VIN * R2 / (R1 + R2)
e.g. 5V input, 2 x 1 k Ohm Resistors
5V * 1k / (1k + 1k) ... 5V * 1k/2k ... 5V * 0.5
= 2.5V = VOUT