A charged capacitor when connected to uncharged one

In summary, the conversation discusses the energy of a system involving two capacitors, one with a capacitance of 10 uF and a potential difference of 150V, and the other with a capacitance of 5 uF. The question is raised whether the energy should be equal in both cases, but the solution shows that there is a decrease in energy when the capacitors are connected. It is noted that this is due to energy losses in the connecting wires.
  • #1
r0ss
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Homework Statement


A capacitor of capacitance 10 uF is raised to a potential difference of 150V. After disconnecting from the battery, it is connected to a capacitor of capacitance 5 uF. Find the energy of the system.

Homework Equations


Energy supposed to be equal in the first case and second case right? But the solution showed that the energy is decreased as the capacitor is connected with uncharged one. Which one is right?

The Attempt at a Solution


Solution for first assumption: 0.1125 J.
Solution for the second: 0.075 J.
 
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  • #2
r0ss said:
Energy supposed to be equal in the first case and second case right? But the solution showed that the energy is decreased as the capacitor is connected with uncharged one. Which one is right?
There will be an energy loss, which is dissipated in the non-zero resistance of the connecting wires. If you search on Google saying "Energy losses on connecting two capacitors", you will get tons of results, like this one.
 
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FAQ: A charged capacitor when connected to uncharged one

What is a capacitor?

A capacitor is an electronic component that stores electrical energy in the form of an electric field. It consists of two conductive plates separated by an insulating material, called a dielectric.

How does a capacitor become charged?

A capacitor becomes charged when a voltage is applied across its plates. This causes one plate to accumulate positive charge and the other to accumulate negative charge, creating an electric field between them.

What happens when a charged capacitor is connected to an uncharged one?

When a charged capacitor is connected to an uncharged one, the charged capacitor will discharge and transfer some of its stored energy to the uncharged capacitor. The amount of charge and voltage on both capacitors will equalize until they reach the same potential.

What is the resulting voltage when a charged capacitor is connected to an uncharged one?

The resulting voltage when a charged capacitor is connected to an uncharged one will be the average of the two initial voltages. This is because the total energy of the system must remain constant, so the voltage and charge will distribute equally between the two capacitors.

Can a charged capacitor be connected to another charged capacitor?

Yes, a charged capacitor can be connected to another charged capacitor. The resulting voltage and charge on each capacitor will depend on their individual capacitances and initial voltages. The total energy of the system will still remain constant.

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