Electric Charges Homework: Potential Difference & Capacitance

In summary, the question is asking which option is true regarding the change in electric charge, potential difference, and capacitance when the plate separation is doubled while the battery remains connected. The correct answer is option c) as the potential difference between the plates is directly proportional to the plate separation. This means that when the plate separation is doubled, the potential difference also doubles. This is due to the function of a battery, which is to maintain a constant potential difference between the plates. The potential difference between the plates also affects the electric field between them, which is directly proportional to the plate separation according to Gauss' law. Lastly, the charge on a plate is also affected by the electric field between the plates, meaning that when the plate separation is
  • #1
science.girl
103
0

Homework Statement


Two parallel conducting plates, separated by a distance d, are connected to a battery of emf [tex]\epsilon[/tex]. Which of the following is correct if the plate separation is doubled while the battery remains connected?
a. The electric charge on the plates is doubled.
b. The electric charge on the plates is halved.
c. The potential difference between the plates is doubled.
d. The potential difference between the plates is halved
e. The capacitance is unchanged.

Homework Equations


[tex]\Delta[/tex]V = [tex]\epsilon[/tex] - Ir

The Attempt at a Solution


I'd actually appreciate it if someone could explain this question to me. I'm having some difficulty with these concepts. What exactly is the question asking? I can probably take it from there.
 
Last edited:
Physics news on Phys.org
  • #2
The question is asking which option is true. That was easy. But the function of a battery is to maintain a constant potential difference between the two plates. What does that tell you about options c) and d)? Now what does the potential difference between the plates have to do with the E field between the plates and their separation? Finally what does the charge on a plate have to do with the E field between the plates? Think Gauss' law.
 
  • #3
Dick said:
The question is asking which option is true. That was easy. But the function of a battery is to maintain a constant potential difference between the two plates. What does that tell you about options c) and d)? Now what does the potential difference between the plates have to do with the E field between the plates and their separation? Finally what does the charge on a plate have to do with the E field between the plates? Think Gauss' law.

Thank you very much! I understand now :smile:
 

FAQ: Electric Charges Homework: Potential Difference & Capacitance

1. What is potential difference?

Potential difference, also known as voltage, is the difference in electric potential energy between two points in an electric field. It is measured in volts (V) and represents the amount of work needed to move a unit of electric charge from one point to another.

2. How is potential difference calculated?

Potential difference can be calculated by dividing the change in electric potential energy by the amount of charge that has moved between two points. In equation form, it is written as V = ΔPE/q, where V is the potential difference, ΔPE is the change in electric potential energy, and q is the amount of charge in Coulombs (C).

3. What is capacitance?

Capacitance is a measure of an object's ability to store electric charge. It is defined as the ratio of the amount of electric charge stored on an object to the potential difference across the object. It is measured in Farads (F) and is represented by the symbol C.

4. How is capacitance calculated?

Capacitance can be calculated by dividing the amount of charge stored on an object by the potential difference across the object. In equation form, it is written as C = q/V, where C is the capacitance, q is the charge, and V is the potential difference.

5. How does capacitance affect the potential difference?

The potential difference across an object is directly proportional to its capacitance. This means that as the capacitance increases, the potential difference also increases. The relationship between capacitance and potential difference is described by the equation V = q/C, where V is the potential difference, q is the charge, and C is the capacitance.

Back
Top