A query about this electrical circuit symbol

[ellieee]

Homework Statement

I'm not sure what this symbol means

Relevant Equations

V1 = R1 / R1+R2+R3 x "inverted 3"

 

[phinfinity]

The epsilon symbol ($\epsilon$) stands for "emf" or ElectroMotive Force. I think it's a bit of a technicality to name voltage sources like batteries with $\epsilon$ while potential difference generated across other components are labeled as Voltage (V).

 

[Steve4Physics]

The epsilon symbol ($\epsilon$) stands for "emf" or ElectroMotive Force. I think it's a bit of a technicality to name voltage sources like batteries with $\epsilon$ while potential difference generated across other components are labeled as Voltage (V).

I know I'm being pedantic but can I add:

1) It is $\mathscr E$ not an epsilon ($\epsilon$). The symbol is a 'script E'. My school physics teacher used to call it a 'curly E'. (To get the symbol with Latex, use \mathscr E.)

2) There is an important difference between the voltage (more correctly terminal pd), V, of a voltage-source and the source's emf $\mathscr E$.

If the voltage-source has some internal resistance, then when a current flows V is smaller than $\mathscr E$. But for an ideal voltage-source (zero internal resistance) V and $\mathscr E$ are the same value. Most simple circuit problems assume an ideal voltage-source; in that case you don't need to worry about the difference.