Chapter 35, Problem 34A

Harry asks whether a battery will run down slower or faster when it connects to a pair of bulbs in series or to the same pair in parallel. He looks to you for an answer. What is your answer?

To determine

Whether the battery runs down slower or faster for parallel or series connection of the bulbs with battery.

Explanation of Solution

Introduction:

The equivalent resistance in the series circuit always remains greater than each resistance of series combination. The equivalent resistance in the parallel circuit always remains less than each resistance of parallel combination. Lesser current passes through the series circuit than the current in a parallel circuit due to greater equivalent resistance than that of parallel connection.

The current can easily pass through the bulbs in the parallel circuit. So, the bulbs in parallel connection draw current at a faster rate and the battery runs down faster.

The current cannot easily pass through the bulbs in the series circuit. So, the bulbs in series connection draw current at a slower rate and the battery runs down slower.

Conclusion:

The battery runs down slower for series connection of the bulbs and the battery runs down faster for parallel connection of the bulbs.