Which statement is true about the relationship between the source current and the branch currents in a parallel circuit?

Which statement is true about the relationship between the source current and the branch currents in a parallel circuit?

• A. The source current is the same as the current in the largest branch
• B. The source current is the same as the current in the smallest branch
• C. The source current equals the average of branch currents
• D. The source current equals the sum of the currents in all branches

Answer: (D)

In a parallel circuit, the current from the source is shared among the branches, but charge is conserved at the junctions. This means the total current leaving the source must equal the sum of the currents through each branch. So the source current is I_total = I_branch1 + I_branch2 + ... + I_branchN. The current in each branch depends on that branch’s impedance (for resistors, I_branch = V/R_branch), but no single branch current can equal the source current unless there is only one branch. That’s why the statement that the source current equals the sum of all branch currents is the correct description.

In a parallel circuit, the current from the source is shared among the branches, but charge is conserved at the junctions. This means the total current leaving the source must equal the sum of the currents through each branch. So the source current is I_total = I_branch1 + I_branch2 + ... + I_branchN. The current in each branch depends on that branch’s impedance (for resistors, I_branch = V/R_branch), but no single branch current can equal the source current unless there is only one branch. That’s why the statement that the source current equals the sum of all branch currents is the correct description.