Finding Energy Stored in a Capacitor

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To find the energy stored in a capacitor in steady state, the correct formula is U = (1/2)CV^2, where C is capacitance and V is voltage. The user initially calculated energy using U = (Q^2)/2C, based on the charge found through loop law, but received incorrect results. The discussion emphasizes the importance of showing work to identify errors in calculations. Clarification on the relationship between charge, voltage, and capacitance is also highlighted. Understanding these principles is essential for accurately determining energy stored in capacitors.
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Homework Statement



How to find the energy stored in the capacitor in steady state in this circuit.

IMG_20160108_210548_HDR.jpg


Homework Equations

The Attempt at a Solution


I found out the charge on the capacitor in steady state using loop law and did energy stored = (Q^2)/2C. but its coming out to be incorrect.
 
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le@rner said:

Homework Statement



How to find the energy stored in the capacitor in steady state in this circuit.

View attachment 94102

Homework Equations

The Attempt at a Solution


I found out the charge on the capacitor in steady state using loop law and did energy stored = (Q^2)/2C. but its coming out to be incorrect.
What is the expression for energy in terms of C and V? In steady state, voltage and capacitance will be known to you.
 
cnh1995 said:
What is the expression for energy in terms of C and V? In steady state, voltage and capacitance will be known to you.

But we also know the charge on the capacitor in steady state. Don't we?
Then why is it coming incorrect using this method.
 
le@rner said:

Homework Statement


How to find the energy stored in the capacitor in steady state in this circuit.
View attachment 94102

Homework Equations



The Attempt at a Solution


I found out the charge on the capacitor in steady state using loop law and did energy stored = (Q^2)/2C. but its coming out to be incorrect.
You need to show your work. We can't say much about what you did wrong if we don't know what you did.
 
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