Physics
Physics
Problem
Explain qualitatively how the currents in each branch of a parallel circuit containing two resistors change if the resistance of one branch is doubled while the applied voltage remains the same.Intuitive explanation
In a parallel circuit, each branch "sees" the full applied voltage independently, so current through each resistor is determined by Ohm's law: . When you double one resistor's value, that branch's current is cut in half—but here's the key insight: the other branch is completely unaffected because it still experiences the same voltage. The total current from the battery increases slightly since one path becomes more restrictive, but each branch responds only to its own resistance change.
Intuitive explanation
In a parallel circuit, each branch "sees" the full applied voltage independently, so current through each resistor is determined by Ohm's law: . When you double one resistor's value, that branch's current is cut in half—but here's the key insight: the other branch is completely unaffected because it still experiences the same voltage. The total current from the battery increases slightly since one path becomes more restrictive, but each branch responds only to its own resistance change.