How does exactly higher capacitance have more bang for your buck ?

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SUMMARY

The discussion centers on the relationship between capacitance, charge, and energy storage in capacitors. It clarifies that capacitance (C) is defined as the charge (Q) stored per unit potential (V), expressed as C=Q/V. The energy stored in a capacitor is calculated using the formula W = 1/2 * C * V^2, demonstrating that higher capacitance allows for more charge to be stored at a given voltage, resulting in greater energy storage. The concept of "more bang for your buck" refers to the efficiency of energy storage relative to the charge and voltage applied.

PREREQUISITES
  • Understanding of basic electrical concepts, including voltage, charge, and energy.
  • Familiarity with the formula for capacitance, C=Q/V.
  • Knowledge of energy storage equations, specifically W = 1/2 * C * V^2.
  • Basic grasp of units such as farads, coulombs, and volts.
NEXT STEPS
  • Study the derivation and implications of the energy storage formula W = 1/2 * C * V^2.
  • Explore practical applications of capacitors in circuits, focusing on energy efficiency.
  • Learn about the effects of varying capacitance in different circuit configurations.
  • Investigate the relationship between capacitance and other components, such as resistors and inductors, in AC circuits.
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Electronics students, electrical engineers, and hobbyists interested in understanding capacitor functionality and energy storage efficiency.

The_Lobster
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How does exactly higher capacitance have "more bang for your buck"?

Hi!

I'm trying to really grasp the concept of capacitance. Whenever I see a description of the definition, [tex]C=Q/V[/tex], they always say either: "More charge stored per potential", or "more bang for your buck".

I don't really see how more charge per potential relates to more energy in the capacitor?

By using [tex]W = 1/2 * C * V^2[/tex], we get the same amount of energy if V = 2V and Q = 4C, as if V = 4V and Q = 2C (in the former case C = 2F, and in the latter C = 0.5F).

Could anyone please clarify why having more charge per potential means "more energy is stored"? or how that relates to having "more bang for your buck"?.

Also, keeping in mind that potential is potential energy per unit charge, [tex]U = qV[/tex], shouldn't there be more potential energy all together if there is more charge AND more potential?

Sorry if this should be simple stuff! I just feel every definition I've read jumps over exactly *why* more charge per potential means more energy stored...
 
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If C is 1 farad and you charge to 1 volt then you have 1 coulomb of charge. If C is 2 farads and you charge to 1 volt then you have 2 coulombs.

Charge per potential
Coulombs per potential
coulombs per volt
Q per volt
Q per V
Q/V

All identical, I just replaced words wit symbols.
 

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