About uniform electric field between parallel plates

[curiosity colour]

I have learned that the electric field between parallel plates are independent of distance
since E=V/d
so if I increase the distance between parallel plates, the E will decrease, right?
if I am right on the previous statement, then why does the electric field are independent of distance?

 

[Drakkith]

I have learned that the electric field between parallel plates are independent of distance

Are you sure that isn't for ideal infinitely long parallel plates?

 

[member 587159]

Are you sure that isn't for ideal infinitely long parallel plates?

You are right. This is only for such plates and can be derived using Gauss' law. If we neglect rand effects, we can still use it as an approximation for smaller plates, though.

 

[curiosity colour]

Are you sure that isn't for ideal infinitely long parallel plates?

The textbook just wrote parallel plates, didn't said anything about ideal infinitely long parallel plates
So only if parallel plates are infinitely long, the electric field between parallel plates are independent of distance ? Still though, why is that?

 

[member 587159]

The textbook just wrote parallel plates, didn't said anything about ideal infinitely long parallel plates
So only if parallel plates are infinitely long, the electric field between parallel plates are independent of distance ? Still though, why is that?

Do you know Gauss' law? (one of the maxwell equations, $\iint_S \vec E . \vec{dA} = \frac{Q_{enc}}{\epsilon_0}$ where we integrate over a closed surface $S$)

 

[curiosity colour]

Do you know Gauss' law? (one of the maxwell equations, $\iint_S \vec E . \vec{dA} = \frac{Q_{enc}}{\epsilon_0}$ where we integrate over a closed surface $S$)

Yeah, I know about Gauss's law

 

[sophiecentaur]

I have learned that the electric field between parallel plates are independent of distance
since E=V/d
so if I increase the distance between parallel plates, the E will decrease, right?
if I am right on the previous statement, then why does the electric field are independent of distance?

If the plates are insulated, the Potential difference will change as you separate them so the V in "E=V/d" will change. (The Capacitance C will change and V=Q/C applies)
If you connect a source of PD to the plates, to maintain V then E=V/d will apply. So there is no contradiction.

 

[Dale]

I have learned that the electric field between parallel plates are independent of distance
since E=V/d
so if I increase the distance between parallel plates, the E will decrease, right?
if I am right on the previous statement, then why does the electric field are independent of distance?

The E field is independent of the distance, but the voltage is not. The E field is the gradient of the voltage, so if you have the same E field over a larger distance then you have a greater voltage.