Druyd:Knowledge

Capacitor power

Storyboard

To charge a capacitance it is necessary to transfer charges against the electric field, which requires energy. This energy is stored in the capacitance and is recovered the minute the capacitor is discharged.

>Model

ID:(1573, 0)

Capacitor power

Description

Variables

Symbol

Text

Variable

Value

Units

Calculate

MKS Value

MKS Units

$C$

Capacitor capacity

$Q$

Charge

$\sigma$

sigma

Charge density by area

C/m^2

$\epsilon$

epsilon

Dielectric constant

$E_d$

E_d

Electric field, two infinite plates

V/m

$W$

Energy

$w$

Energy density

J/m^3

$dQ$

Infinitesimal charge

$dW$

Infinitesimal variation of work

Calculations

Equation

Number

First, select the equation:

, then, select the variable:

Symbol

Equation

Solved

Translated

Calculations

Symbol

Equation

Solved

Translated

Variable

Given

Calculate

Target :

Equation

To be used

Equations

$ dW = \displaystyle\frac{ Q }{ C } dQ$

dW = Q * dQ / C

None

(ID 11621)

$ W = \displaystyle\frac{ Q ^2 }{ 2 C }$

W = Q ^2 /( 2 * C )

None

(ID 11622)

$ w = \displaystyle\frac{ \sigma ^2 }{2 \epsilon \epsilon_0 }$

w = sigma ^2 /( 2 * e * e_0 )

None

(ID 11624)

$ w = \displaystyle\frac{1}{2} \epsilon \epsilon_0 E_d ^2$

w = e * e_0 E_d ^2 /2

None

(ID 11625)

Examples

ID:(1573, 0)