Capacitance and Effective Electric Field

In summary, capacitance is the ability of a parallel plate capacitor to store charge and voltage between its two plates. The relationship between charge, voltage, and capacitance is expressed by the equation Q=VC or C=Q/V. A larger capacitance means that the capacitor can store more charge for a given input voltage. The presence of a dielectric material between the plates of a capacitor decreases the effective electric field, which in turn increases the capacitance. This is because the lower electric field reduces the force pulling charges across the plates, allowing for a higher charge holding capacity.
  • #1
Hereformore
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Im trying to gain a more conceptual understanding of capacitance.

Capacitance is the ability of a parallel plate capacitor to store charge, and thereby voltage, between its two plates. The more charge the capacitor can store per input voltage, the greater the capacitance.

Hence the relationship:

Q=VC or C=Q/V

For the same amount of charge, a "better" capacitor with a larger capacitance would require less voltage (I am interpreting this right, right? haha).

My question is regarding how capacitance relates to electric field.

The way dielectric materials work is that they decrease the effective electric field between the two parallel plates by getting polarized by the applied field. This polarization lowers the amount of electric filed felt by the charges on the opposite plate. (am I understanding it right until this point?).

My question is, conceptually, how does lowering the electric field between the two plates increase the charge holding capacity, aka capacitance, of the capacitor?

Is it that the stronger the electric field, the greater the force pulling the charges across the space in between the plates and so, the more likely it is that the charges will be able to "jump" across, thereby neutralizing/lowering some of the voltage set up across the capacitor?
 
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  • #2
Thanks for the post! Sorry you aren't generating responses at the moment. Do you have any further information, come to any new conclusions or is it possible to reword the post?
 

FAQ: Capacitance and Effective Electric Field

What is capacitance?

Capacitance is a measure of an object's ability to store electric charge. It is represented by the letter C and is measured in units of Farads (F).

How is capacitance related to effective electric field?

The effective electric field is directly proportional to capacitance. This means that as the capacitance increases, the effective electric field also increases.

What factors affect capacitance?

The factors that affect capacitance include the distance between the two conducting plates, the area of the plates, and the material between the plates. The type of material between the plates is especially important as it determines the dielectric constant, which affects the capacitance value.

How is capacitance calculated?

Capacitance can be calculated using the formula C = Q/V, where Q is the charge stored and V is the voltage across the plates. It can also be calculated using the formula C = εA/d, where ε is the dielectric constant, A is the area of the plates, and d is the distance between the plates.

What is the purpose of capacitance in circuits?

Capacitance is an essential component in electronic circuits as it can store and release electrical energy. It is used in various applications, such as smoothing voltage fluctuations, filtering signals, and storing data in memory devices.

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