Rankers Physics
Topic: Capacitors
Subtopic: Parallel Plate Capacitor

Ten capacitors are joined in parallel and charged with a battery up to a potential V. They are then disconnected from the battery and joined in series. Then, the potential of this combination will be:
1 V
10 V
5 V
2 V

Solution:

Let's analyze the problem step by step and derive why the potential difference is 10 V.


1. Capacitors in Parallel (Initial Condition)

When the 10 capacitors, each with capacitance CC, are connected in parallel:

  • The equivalent capacitance is: Cparallel=10CC_{\text{parallel}} = 10C
  • The total charge stored when connected to a battery of potential VV is: Q=CparallelV=(10C)V=10CVQ = C_{\text{parallel}} \cdot V = (10C) \cdot V = 10CV

2. Capacitors in Series (Reconfigured System)

After disconnecting the battery, the capacitors are joined in series:

  • The equivalent capacitance for 10 capacitors in series is: Cseries=C10C_{\text{series}} = \frac{C}{10}
  • The charge QQ stored on the series combination remains the same (as charge is conserved): Qseries=Q=10CVQ_{\text{series}} = Q = 10CV

3. Potential Across the Series Combination

The potential difference across a capacitor or combination of capacitors is related to the charge QQ and capacitance CC:

Vseries=QCseriesV_{\text{series}} = \frac{Q}{C_{\text{series}}}

Substitute Q=10CVQ = 10CV and Cseries=C10C_{\text{series}} = \frac{C}{10}:

Vseries=10CVC10=VV_{\text{series}} = \frac{10CV}{\frac{C}{10}} = V

Thus, the potential across the series combination is V=10VV = 10V,.


Final Answer:

The potential of the series combination is:

10V\boxed{10V}

Leave a Reply

Your email address will not be published. Required fields are marked *