Plates of capacitors and dielectric constant

In summary, when a dielectric is inserted between the plates of a capacitor, the charge remains the same while the values of capacitance and voltage change. This is correct as long as the capacitor is isolated and no charge can enter or leave the plates. This concept is related to the conservation of charges and is often studied in electrostatics.
  • #1
gracy
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In my textbook it is written that
Electric charge on plates of capacitors (without dielectric ) is Q=CV
And when dielectric is inserted in the space between plates of capacitors .charge Q remains the same whereas values of C and V change.
i.e Q=C'V'
is it correct?
 
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  • #2
gracy said:
In my textbook it is written that
Electric charge on plates of capacitors (without dielectric ) is Q=CV
And when dielectric is inserted in the space between plates of capacitors .charge Q remains the same whereas values of C and V change.
i.e Q=C'V'
is it correct?
Yes.
Do you know conservation of charges?
You might have studied in electrostatics?
 
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  • #3
Yes, provided that the capacitor is isolated (i.e. not connected to a circuit) so no charge can enter or leave the plates.
 
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  • #4
Raghav Gupta said:
Yes.
jtbell said:
Yes, provided that the capacitor is isolated (i.e. not connected to a circuit) so no charge can enter or leave the plates.
Thanks a lot for quick reply.
 
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1. What is a capacitor?

A capacitor is an electronic component that stores electrical energy by accumulating opposite charges on two conductors separated by an insulating material, known as a dielectric.

2. How do plates affect the capacitance of a capacitor?

The capacitance of a capacitor is directly proportional to the surface area of its plates. Increasing the size of the plates will result in a higher capacitance, while decreasing the size will result in a lower capacitance.

3. What is the formula for calculating the capacitance of a capacitor with dielectric material?

The formula for calculating the capacitance of a capacitor with dielectric material is C = k * ε0 * A/d, where k is the dielectric constant, ε0 is the permittivity of free space, A is the surface area of the plates, and d is the distance between the plates.

4. How does the dielectric constant affect the capacitance of a capacitor?

The dielectric constant is a measure of the ability of a material to store electrical energy in an electric field. A higher dielectric constant will result in a higher capacitance, as it allows for more charge to be stored on the plates.

5. What are some common materials used as dielectrics in capacitors?

Some common materials used as dielectrics in capacitors include air, paper, mica, ceramic, and various types of plastic. The choice of dielectric material depends on the specific application and desired capacitance value.

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