Practice question · Multiple choice
Adding a resistor in parallel DECREASES total resistance while adding one in series increases it. Why do the two arrangements differ in sign?
Hints
- Think of lanes on a motorway rather than of formulas.
- Ask what total current does when a new branch is added.
Show the answer
C. Because a parallel branch opens an additional path for current
Why
More paths means more total current for the same voltage, and resistance is voltage over current. The reciprocal formula is the consequence, not the reason.
Practise Current, Resistance, and DC Circuits
The app has 8 more questions on this lesson, and keeps your place in the course. Physics I is free to start.