(E&M) Charge and electric field in a two plate system.

[Chewy247]

1. Two metal plates, 10 mm thick, are held a distance z=40 mm apart with a potential difference of 10 V across them. As you look at them the positive plate is on the left. In between the plates is a vacuum. Ignoring edge effects and assuming unit area for the plates, calculate both the charge and the electric field within this system. Hence, plot a graph of charge density against position across the 60 mm from the back of one plate to the back of the other. Hence draw a graph of electric field against position over the same range.2. Homework Equations ?
3. The Attempt at a Solution - did but got stupid answers.

 

[berkeman]

1. Two metal plates, 10 mm thick, are held a distance z=40 mm apart with a potential difference of 10 V across them. As you look at them the positive plate is on the left. In between the plates is a vacuum. Ignoring edge effects and assuming unit area for the plates, calculate both the charge and the electric field within this system. Hence, plot a graph of charge density against position across the 60 mm from the back of one plate to the back of the other. Hence draw a graph of electric field against position over the same range.


2. Homework Equations ?



3. The Attempt at a Solution - did but got stupid answers.

Welcome to the PF.

What is the electric field inside the conductors themselves (inside the plates, from back to front)?

What is the value of the electric field between the plates? You are given the numbers 10V and 40mm apart. What are the units of electric field?...

 

[Chewy247]

electric field between the plates: V/D = 250 v/m is that right? for the plates that would be 1000 v/m. you see that's where I started thinking wtf.

 

[berkeman]

electric field between the plates: V/D = 250 v/m is that right? for the plates that would be 1000 v/m. you see that's where I started thinking wtf.

Correct on the field strength between the plates. Remember, though, that there can be no electric field inside of a conductor...

 

[Chewy247]

Great. I've got it sussed now. Thanks for the hint my man!

 

[tombrown9g2]

1. Two metal plates, 10 mm thick, are held a distance z=40 mm apart with a potential difference of 10 V across them. As you look at them the positive plate is on the left. In between the plates is a vacuum. Ignoring edge effects and assuming unit area for the plates, calculate both the charge and the electric field within this system. Hence, plot a graph of charge density against position across the 60 mm from the back of one plate to the back of the other. Hence draw a graph of electric field against position over the same range.


2. Homework Equations ?



3. The Attempt at a Solution - did but got stupid answers.

do you by any chance do physics at the university of hull ;)

 

[Chewy247]

Hahah Yeah I do. Do you happen to have gone there in the past? Coz I've never heard of a tom brown.

 

[tombrown9g2]

Hahah Yeah I do. Do you happen to have gone there in the past? Coz I've never heard of a tom brown.

haha no I am there now in 1st year, recognised a question from the em assignment and figured it most be someone in my class lol. Tom Brown is just a nickname, real name is chris. I am the tall guy with glasses, usually sits near the back :)

 

[Chewy247]

Tall guy with glasses, can't say I've noticed ya... I must be too busy swatting or sleeping in lectures. lol I'm the guy that knocks around with the old git and the ****-knuckle in the halo reach hoodie, also near the back.

 

[berkeman]

Please take the off-topic conversation to PMs guys. Thanks.