Calculate the energy in a capacitor's electric field

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SUMMARY

The energy stored in a capacitor's electric field can be calculated using the formula E = q²/(2*C). In this discussion, a capacitor with a charge of 0.008C and a capacitance of 2 μF was analyzed. The correct calculation yields an energy of 16J, contradicting the stated answer of 32J, indicating a likely error in the original problem statement.

PREREQUISITES
  • Understanding of capacitor fundamentals
  • Familiarity with the formula E = q²/(2*C)
  • Basic knowledge of electrical charge and capacitance
  • Ability to perform unit conversions (e.g., microfarads to farads)
NEXT STEPS
  • Review the principles of energy storage in capacitors
  • Learn about common mistakes in capacitor energy calculations
  • Explore the implications of charge and capacitance on energy storage
  • Investigate advanced capacitor applications in electrical circuits
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Students studying electrical engineering, educators teaching capacitor theory, and anyone involved in electronics who needs to understand energy calculations in capacitors.

MisterP
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Homework Statement


Capacitor has a charge of 0.008C. Capacity is 2 μF. Need to calculate energy of electric field. Answer: 32J

Homework Equations


E = q2/2*C

The Attempt at a Solution


This seems right equation, but instead of 32J I get 16J.. any ideas?
 
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MisterP said:

Homework Statement


Capacitor has a charge of 0.008C. Capacity is 2 μF. Need to calculate energy of electric field. Answer: 32J

Homework Equations


E = q2/2*C

The Attempt at a Solution


This seems right equation, but instead of 32J I get 16J.. any ideas?

I think you are correct and the stated answer is wrong. Unless I am missing some conceptual insight, I believe they have made a calculation error.
 

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