In a parallel circuit, all load elements have the same voltage across them. Current has multiple ways to flow through the different branches. Therefore, current flow is less in different parallel parts of the circuit. Here’s how it works.
The circuit below has three identical resistors in parallel. Current flows from the positive terminal of the battery to the negative terminal. The current can flow through multiple branches at once. So the total resistance of the circuit is lower than the summed resistor values.
The voltage drop across the resistors is equal to the voltage in (Vin = +12V).
We need to know the current flowing through by the circuit. Let’s simply apply Ohm’s law. Before we can do that, we need the total resistance of the circuit. In a parallel circuit, we use the following formula.
So the total resistance of the circuit is
How much current through a single branch?
If we now apply Ohm’s law as before, we can find the current flow through one resistor. Let’s take the first one.
Now since all the resistor values in this example are the same, we only need to add up the current through all resistors.