The sum of all potential changes in a closed circuit is zero. This is called _____________.

The Correct answer is Kirchhoff's second rule.

Key Points

• Kirchhoff's second rule, also known as the Voltage Law (KVL), states that the algebraic sum of all potential differences (voltages) around any closed loop in a circuit is zero.
• This rule is based on the law of conservation of energy, which implies that the total energy gained and lost by charges in a closed circuit must balance.
• The equation derived from this rule is: ΣV = 0, where V represents the voltage.
• The potential changes include contributions from resistors, batteries, and other elements in the circuit.
• This rule is widely applied in circuit analysis to calculate unknown voltages and currents in complex circuits.
• Gustav Kirchhoff, a German physicist, formulated this rule in 1845.
• It complements Kirchhoff’s first rule (current law) to provide a complete framework for analyzing electrical circuits.

 Additional Information

• Kirchhoff's fourth rule
  • There is no fourth rule in Kirchhoff's laws. Kirchhoff's contributions are limited to the current law (first rule) and the voltage law (second rule).
  • Any mention of a fourth rule is likely a misinterpretation or fictional addition.
• Kirchhoff's first rule
  • Kirchhoff's first rule is the Current Law (KCL), which states that the sum of currents entering a junction equals the sum of currents leaving the junction.
  • This is based on the conservation of electric charge.
• Kirchhoff's third rule
  • Similar to the "fourth rule," there is no separate third rule attributed to Kirchhoff.
  • The first and second rules are the only fundamental laws established by him for circuit analysis.