Answer: I1 + I2 (algebraically, respecting direction).
- A I1 + I2 usually, regardless of the direction each current actually flows
- B I1 + I2 (algebraically, respecting direction)
- C I1 x I2, multiplying the two branch currents together
- D max(I1, I2), taking mainly whichever current is larger in magnitude
Correct answer: B. I1 + I2 (algebraically, respecting direction)
Explanation: Superposition theorem: actual current = algebraic sum of individual currents. Directions matter. Add I1 and I2 with proper signs.
In series, the same current flows through both resistors; in parallel, the current splits between branches and the voltage across each resistor is the same.
Concept context
Ohm's law, resistors, Kirchhoff's laws, Wheatstone bridge, and cells.