Confusion about Dielectrics and Potential Difference in Capacitors

  • Thread starter KayleighK
  • Start date
  • Tags
    Dielectrics
In summary, the conversation discusses the concept of adding a dielectric between two capacitors. It is stated that this will increase the potential difference between the plates and the capacitance by decreasing the potential difference (V) according to the equation C=Q/V. This leads to confusion as decreasing V should decrease the potential difference, not increase it. The conversation concludes that there may be a misprint in the textbook.
  • #1
KayleighK
8
0
I'm reading my physics textbook right now and it states that when you add a dielectric between two capacitors you are:
1. Increasing the potential difference between the two plates.
2. Increasing capacitance by decreasing V (Q/V=C)

Isn't this contradictory? I thought that V in the equation (Q/V=C) was the potential difference between the capacitor plates. Therefore, if you decrease V, you woul be lowering the potential difference between the plates, not increasing it. Can someone explain this to me? Thank you.
 
Physics news on Phys.org
  • #2
It is contradictory.
The effect of inserting a dielectric material between the plates of a charged capacitor, is to reduce the pd between those plates. (Charge stays constant)
This has the effect of increasing the capacitance.
C=Q/V so if you decrease V you increase C.
It must be a misprint.
 

1. What is a dielectric material?

A dielectric material is a type of substance that is able to store electrical energy within an electric field. It is considered an insulator because it does not allow a significant flow of electric current.

2. How do dielectrics affect electric fields?

Dielectrics can affect electric fields by reducing the strength of the electric field. This is because they contain electric dipoles, which align with the external electric field and create an opposing field, thus weakening the overall electric field.

3. What is the dielectric constant?

The dielectric constant, also known as the relative permittivity, is a measure of a material's ability to store electrical energy in an electric field. It is the ratio of the electric permittivity of a specific material to the electric permittivity of a vacuum.

4. How are dielectric materials used in capacitors?

Dielectric materials are commonly used in capacitors to increase their capacitance, or ability to store electrical charge. By placing a dielectric material between the plates of a capacitor, the electric field is strengthened, and the capacity to store charge is increased.

5. Are there different types of dielectric materials?

Yes, there are many different types of dielectric materials, including ceramics, plastics, and liquids. Each type has different properties and is used for specific applications based on their dielectric constant, dielectric strength, and other factors.

Similar threads

I Why is a Dielectric slab ejected from the capacitor when energized?
    • Electromagnetism
Replies
10
Views
1K
I Is capacitor energy the electrostatic energy of the whole system?
    • Electromagnetism
Replies
9
Views
1K
Confused by capacitors and potential energy
    • Electromagnetism
Replies
7
Views
7K
Two different dielectrics between parallel-plate capacitor
    • Introductory Physics Homework Help
Replies
6
Views
316
A capacitor with two dielectrics in series
    • Electromagnetism
Replies
6
Views
4K
Help clarifying capacitors, dielectrics, E field, potential
    • Electromagnetism
Replies
2
Views
970
Energy changes upon insertion of a solid dielectric in a capacitor
    • Electromagnetism
Replies
2
Views
1K
A Capacitor With A Dielectric But Also Free Space in Between
    • Electromagnetism
Replies
5
Views
1K
I Capacitor connected to voltage source, vary plate separation
    • Electromagnetism
Replies
9
Views
504
Exploring Potential Differences between Conductors of the Same Charge
    • Electromagnetism
Replies
5
Views
1K

Hot Threads

Recent Insights

Back
Top