Voltages around any closed loop sum to zero because energy is conserved.
Around any closed loop the algebraic sum of voltage rises and drops is zero: ΣV=0. It expresses energy conservation. Loop equations or mesh analysis rely on it.
12 V source with two resistors: 12 = V₁+V₂.
This law is the basis of loop analysis and tells you that voltage drops must add up around any closed path.
Voltages around any closed loop sum to zero because energy is conserved.
This law is the basis of loop analysis and tells you that voltage drops must add up around any closed path.
Pick a loop direction, then treat a voltage as positive if you meet it going from minus to plus. Apply the same rule consistently.
Not in the simple lumped form. Induced EMFs in loops must be added as sources, which is why the physical field needs to be considered.
Typical applications include checking the voltage drop across a battery and a chain of resistors, writing loop equations for a multi-battery circuit and verifying an unexpected reading on a test board.
Study "Kirchhoff's current law" first (topic 10 of 106 in Electrical Engineering). It covers the groundwork this topic builds on.
Follow the loop direction consistently. Resistor drop is IR in direction of current. Works with AC phasors too.
12 V source with two resistors: 12 = V₁+V₂.
The next topic is "Voltage and current dividers", which builds directly on this one.
It is classed as Beginner in Electrical Engineering (topic 11 of 106). It is an entry-level topic. It relies only on basic school mathematics and the ideas introduced earlier in this discipline.
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