## Homework Statement

Draw a circuit the involves a battery and two identical bulbs that will maximize the lifetime of the battery. More specifically, draw a circuit that allows you to run the lights longest

## Homework Equations

P = IV
V = IR
Series: R = R1 + R2
Parallel: R = 1/(1/R1 + 1/R2)

## The Attempt at a Solution

I know that the equivalent resistance of the light bulbs in series is greater than the equivalent resistance in parallel. I also know that the battery provides a fixed emf. In series, there is a smaller current and a larger resistance than in parallel. I think that because parallel circuits have less resistance, if I put the light bulbs in parallel, then the battery life will be maximized. Does this make sense, or am I woefully lost in circuits? Thank you so much.

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## Homework Statement

Draw a circuit the involves a battery and two identical bulbs that will maximize the lifetime of the battery. More specifically, draw a circuit that allows you to run the lights longest

## Homework Equations

P = IV
V = IR
Series: R = R1 + R2
Parallel: R = 1/(1/R1 + 1/R2)

## The Attempt at a Solution

I know that the equivalent resistance of the light bulbs in series is greater than the equivalent resistance in parallel. I also know that the battery provides a fixed emf. In series, there is a smaller current and a larger resistance than in parallel. I think that because parallel circuits have less resistance, if I put the light bulbs in parallel, then the battery life will be maximized. Does this make sense, or am I woefully lost in circuits? Thank you so much.
The voltage is a constant determined by the battery. The battery lasts the longest when there is the least amount of power getting used. Since P=IV and the voltage drop across the entire circuit is a constant determined by the battery, then the current is the only factor left. Is the current high when there is a large or small resistance?

If you put the bulbs in parallel, will they draw more current or less current?

If the bulbs draw more current, will the battery be able to supply energy for a greater or lesser period of time?

(Hint: You want to minimize the rate of energy dissipation from the battery.)

EDIT: NotMrX has said basically the same things, a few minutes before me.

Because V = IR, and I = V/R, then the larger current will coincide with the smaller resistance (parallel circuit). If the parallel circuit has a small resistance and larger current, then it will use up more power, so the series circuit maximizes battery life, right? Thanks.