The dielectric contains polar molecules, that is molecules which have a + and a - side. So they align with the electric field (e.g. + side of molecule toward - plate). This means the dielectric experiences a force toward the plates. The force depends on the number and degree of polarity of the molecules in the dielectric, which determines the k of the permitivity.davidY said:suppose you had a capacator and a free to move dialetric, which was outside of it, and you attatch a voltage to the capacator. the dialetric will move in. however, does anybody know what force and where the force is that causes the dialetric to move in?
No. The molecules in the dielectric are affected by the entire field of the plate. Have a look at this, for example:davidY said:thanks. by the way, would it be the fringing effects of the electric fields that cause the fnorce? (as the non fringing electric field would be pointing in the direction of one plate to another)
A capacator with moving dielectric is an electronic device that consists of two conductive plates separated by a dielectric material, which can be moved to change the distance between the plates. This results in a change in capacitance and allows for the storage and release of electrical energy.
The movement of the dielectric material between the plates changes the distance between them, which in turn changes the electric field and capacitance. When the dielectric is moved closer to the plates, the capacitance increases, and when it is moved farther away, the capacitance decreases. This allows for the storage and release of electrical energy as needed.
Capacators with moving dielectrics are commonly used in variable capacitors, which can be found in radio tuning circuits and electronic filters. They are also used in electronic devices that require variable capacitance, such as sensors and switches.
The capacitance of a capacator with moving dielectric can be calculated using the formula C = εA/d, where C is the capacitance, ε is the permittivity of the dielectric material, A is the area of the plates, and d is the distance between the plates. As the distance changes, the capacitance also changes accordingly.
One limitation of a capacator with moving dielectric is that it may not be able to handle high voltages, as the movement of the dielectric material can cause arcing between the plates. Additionally, the movement of the dielectric may also introduce unwanted noise or interference in the circuit. These limitations can be addressed through proper design and use of other electronic components.