Which equation correctly expresses the total current IT when the currents in all branches are known?

Which equation correctly expresses the total current IT when the currents in all branches are known?

• A. IT = I1 + I2 + I3 + ⋯ IN
• B. IT = I1 × I2 × I3 × ... IN
• C. IT = I1 − I2 − I3 − ... IN
• D. IT = I1 = I2 = I3 = ... IN

Answer: (A)

In a parallel circuit, the supply current splits into the different branches and then recombines back into the source. This means the current from the source is the sum of the currents in each branch, following Kirchhoff’s current law at the junction where the branches meet. So the total current is I1 + I2 + I3 + ... + IN. The other forms don’t describe how currents combine in parallel: multiplying currents, subtracting them, or claiming they’re all equal to the total don’t reflect how current distributes across parallel branches.

In a parallel circuit, the supply current splits into the different branches and then recombines back into the source. This means the current from the source is the sum of the currents in each branch, following Kirchhoff’s current law at the junction where the branches meet. So the total current is I1 + I2 + I3 + ... + IN. The other forms don’t describe how currents combine in parallel: multiplying currents, subtracting them, or claiming they’re all equal to the total don’t reflect how current distributes across parallel branches.