Question

As more lamps are put into a series circuit, the overall current in the circuit a. Increasesb. Decreasesc. Remains the same

Answer 1

Answer:

b. Decreases

Explanation:

The total resistance of a series circuit is equal to the sum of the individual resistances:

$R_T=R_1+R_2+...+R_n$ (1)

Therefore, as we add more lamps, the total resistance increases (because we add more positive tems in the sum in eq.(1).

The current in a circuit is given by Ohm's law:

$I=\frac{V}{R_T}$

where V is the voltage provided by the power source and $R_T$ is the total resistance. We notice that the current, I, is inversely proportional to the total resistance: therefore, when more lamps are added to the series circuit, the total resistance increases, and therefore the current in the circuit decreases.