Kirchhoff's voltage law
Also: KVL, loop law
Signed voltage changes sum to zero around a closed circuit loop.
KVL follows conservative electric potential in lumped circuits; rapidly changing magnetic flux requires the full induced-emf model.
- Formula
ΣV = 0 around a loop
Example A 5 V source can balance 2 V and 3 V drops.
Common misconception Voltage does not split equally unless component values and topology make it so.