# How does resistance in a series circuit change when more bulbs are added?

##### 1 Answer
Apr 21, 2014

Resistance increases when bulbs are added to a series circuit.

The total resistance in a series circuit is the sum of all the resistors on the circuit. This is summarized in the formula ${R}_{T} = {R}_{1} + {R}_{2} + {R}_{3} + \ldots$

Perhaps reviewing this excellent video on series circuits will help as well.

http://socratic.org/physics/circuits/resistors-in-series-and-parallel/resistors-in-series-vs-resistors-in-parallel