Apply: what will be the total resistance and current in a parallel circuit with a 15-volt battery and three 10-ohm resistors? test your answers with the gizmo.

1) Total resistance

the total resistance of a circuit with n resistors in parallel is given by

where  are the single resistances.

In our circuit, we have 3 resistors of  each, so the total resistance of the circuit is given by

which means a total resistance of


2) Current in the circuit

The current in the circuit can be found by using Ohm's law:

where V is the voltage of the battery and Req is the total resistance we found before. By using V=15 V, we find

Ithink the answer would be 1,350!

Yes