Which statement correctly describes the current in a parallel circuit?

Which statement correctly describes the current in a parallel circuit?

• A. Vt across the branches equals the total current
• B. Current is the same in all branches
• C. Total current equals the product of branch currents
• D. IT = I1 + I2 + I3

Answer: (D)

In a parallel circuit, the same voltage is across every branch, but the current through each branch can differ depending on each branch’s resistance. The key idea is that current must conserve at the junction: the total current supplied by the source splits into the branch currents, and those branch currents add back together to become the total. So the total current from the source is the sum of the currents in each branch, which for three branches is IT = I1 + I2 + I3. That’s why this relationship correctly describes the system. The other statements don’t fit the behavior of a parallel network: current is not generally the same in all branches, since different branch resistances draw different currents. The total current isn’t the product of branch currents; currents add, not multiply. And the voltage across the branches is the same as the source voltage, not the total current.

In a parallel circuit, the same voltage is across every branch, but the current through each branch can differ depending on each branch’s resistance. The key idea is that current must conserve at the junction: the total current supplied by the source splits into the branch currents, and those branch currents add back together to become the total. So the total current from the source is the sum of the currents in each branch, which for three branches is IT = I1 + I2 + I3. That’s why this relationship correctly describes the system.

The other statements don’t fit the behavior of a parallel network: current is not generally the same in all branches, since different branch resistances draw different currents. The total current isn’t the product of branch currents; currents add, not multiply. And the voltage across the branches is the same as the source voltage, not the total current.