AP Physics 2 / Unit 11: Electric Circuits
11.6 Kirchhoff's Loop Rule
Notes
The sum of potential changes around any closed loop is zero (energy conservation).
- Batteries add voltage (− to +); resistors drop $IR$ in the direction of current.
Practice
A 9 V battery in series with two resistors. One drops 4 V. The other drops:
$9-4$.
The loop rule is based on conservation of:
Energy per charge.
Around a closed loop, the sum of voltage changes:
Return to the same potential.
Ready for more? Take the Unit 11 test.