A capacitor with stored energy 4.0 J is connected with an identical capacitor with no identical capacitor with no electric field in between. Find the total energy stored in the two capacitors.

Given,


The stored energy in the first capacitor is 4.0J


Formula used


Energy stored in a capacitor of capacitance C across a potential difference V is,


Energy stored in the capacitor,


Whenever an uncharged capacitor is connected with a charged capacitor, the charge will redistribute according to the capacitance of both of the capacitors.


In the given case, both the capacitors are identical and hence the charge will distribute equally in both.


We assume that the charge in the first capacitor is initially as q. After the charge distribution, the charge on both capacitors will be q/2.


Since the capacitance are equal and there is no electric field placed in between, according to the eqn.1 the energy stored in both the capacitors are same.


So, by conservation of energy, the total 4J will be distributed to both of the capacitors. So each capacitor will store energy of amount 2J.


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