How do voltage and current behave in a parallel circuit?

• A. Voltage stays the same, current divides proportionally.
• B. Current stays the same, voltage divides proportionally.
• C. Voltage and current both stay the same.
• D. Voltage changes across branches.

Answer: (A)

In a parallel circuit, the same voltage appears across every branch because each branch is tied directly across the same two nodes of the source. The current from the source is the sum of the branch currents, so it “divides” among the branches. How much current goes through each branch is determined by its resistance: with the same voltage across all branches, a branch with lower resistance draws more current (I = V/R), while a branch with higher resistance draws less. So currents split in proportion to the branch conductances (inversely to their resistances), and the total current equals the sum of all branch currents.

That’s why the option stating voltage stays the same and current divides proportionally is the best description. The other ideas don’t fit: the current isn’t generally the same in all branches unless their resistances are identical; the voltage doesn’t divide across branches in a parallel setup; and the voltage across branches isn’t changing from one branch to another in an ideal parallel arrangement.