Why Does a Capacitor's Charge Remain the Same When Voltage is Removed?

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In summary, a capacitor is an electronic device that stores and releases electrical energy. It works by accumulating positive and negative charges on its two plates, creating an electric field that stores energy. There are various types of capacitors, such as ceramic and electrolytic, each with different properties and uses. Capacitance is measured in farads (F) but is often expressed in smaller units like microfarads (μF) and picofarads (pF). The capacitance of a capacitor can be calculated using the formula C=q/V, taking into account the charge, voltage, plate size and distance, and the type of dielectric material.
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Rohan R T
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When voltage supply is removed from a parallel plate capacitor, why does the charge remain as before?
 
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Because the charge has nowhere to go. It can't get through the dielectric, and there's no other path to the other plate.
 
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Rohan R T said:
why does the charge remain as before?

to be a little more specific
The charge on a capacitor never changes, that is, the net charge always = 0

You should get used to using the more correct term of the capacitor being energised
when an external voltage source is applied across the capacitor terminals

Dave
 

FAQ: Why Does a Capacitor's Charge Remain the Same When Voltage is Removed?

What is a capacitor?

A capacitor is an electronic device that stores and releases electrical energy. It is made up of two conductive plates separated by an insulating material called a dielectric.

How does a capacitor work?

When a voltage is applied to a capacitor, one plate accumulates a positive charge while the other accumulates a negative charge. This creates an electric field between the plates, and the capacitor stores energy in this field. When the capacitor is connected to a circuit, it can release this stored energy.

What are the different types of capacitors?

There are many different types of capacitors, including ceramic, electrolytic, film, and tantalum capacitors. Each type has different properties and is used for different purposes.

What are the units of capacitance?

The unit of capacitance is the farad (F). However, capacitors are typically measured in smaller units such as microfarads (μF) and picofarads (pF).

How do I calculate the capacitance of a capacitor?

The capacitance of a capacitor can be calculated using the formula C=q/V, where C is capacitance, q is the charge on the plates, and V is the voltage applied to the capacitor. The capacitance also depends on the size and distance between the plates, as well as the type of dielectric material used.

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