Changing the distance between capacitor plates

[Feodalherren]

Homework Statement

1. The distance between two parallel plates is increased while they remain hooked to a battery. Which one of the following statements is true?

The voltage between the plates will decrease.
The electric field between the plates will increase.
The charge on the plates will decrease.
The capacitance of these two plates will increase.
None of the above.

Homework Equations

The Attempt at a Solution

So for question one,
What does the battery have to do with anything!? That just means that the voltage is constant?

C = εA / d

So if distance is increased the answer is supposed to be that the charge will decrease. What?! Doesn't make any sense. What does the charge have to do with anything? I thought the charge came from the electrons moving around, so why would moving the plates affect the electrons at all?

 

[andre220]

Think about what other equation relates capacitance, charge and voltage

 

[Feodalherren]

C = Q/V

I'm trying to get the physical picture. What exactly is going on here?

I've googled and searched for videos on youtube. I can't find anything that explains it.

 

[CWatters]

If d changes then c changes. Now think about the second eqn.

 

[CWatters]

Perhaps think what would happen if the plates were moved with and without the battery connected. What can and can't change with or without the battery connected and why.