Question

In a simple circuit a 6-volt dry cell pushes charge through a single lamp which has a resistance of 3 Ω. According to Ohms law the current through the circuit is 2Amps.If a second identical lamp is connected in series, the 6-volt battery must push a charge through a total resistance of ________ Ω. The current in the circuit is then __________ Amps.

Answer 1

If a second identical lamp is connected in series, the 6-volt battery must push a charge through a total resistance of 6 Ω. The current in the circuit is then 1 Amp.

Step-by-step explanation

The first circuit was made of a battery and a lamp. Now, a second identical lamp - i.e. with the same resistance, is connected in series, so we have the following circuit,

The equivalent resistance of the circuit is the sum of the resistances of each lamp,

`R_(eq)=R+R=3\Omega+3\Omega=6\Omega`

And, by Ohm's law, the total current through the circuit is,

`I=(V)/(R_(eq))=(6V)/(6\Omega)=1A`

Hence, the total resistance is 6 Ω and the current in the circuit is 1 Amp.