AC Voltage Applied to a Capacitor A capacitor is an electrical device that stores electric charge. It acts like a container that holds onto charge, similar t...
A capacitor is an electrical device that stores electric charge. It acts like a container that holds onto charge, similar to how a water balloon stores air. When the voltage of a DC source is applied across the capacitor, the charges inside the capacitor move in the direction of the applied voltage.
The amount of charge stored by the capacitor depends on the voltage applied and the capacitance of the capacitor itself. The formula for the charge stored by a capacitor is:
where:
is the charge in coulombs
is the capacitance in farads
is the voltage in volts
According to this formula, the charge stored by the capacitor will be directly proportional to the voltage applied and inversely proportional to the capacitance.
The voltage across the capacitor will also be directly proportional to the charge stored by the capacitor. This means that if the charge increases, the voltage will also increase.
The relationship between the voltage, charge, and capacitance can be represented by an equation:
where:
is the voltage in volts
is the charge in coulombs
is the capacitance in farads
This equation shows that the voltage across the capacitor is directly proportional to the charge stored by the capacitor and inversely proportional to the capacitance of the capacitor.
The maximum voltage that a capacitor can withstand is determined by its physical properties. If the voltage applied to a capacitor exceeds this maximum voltage, the capacitor will break down and the charges will leak out.
By controlling the voltage applied to a capacitor, we can control the amount of charge stored by the capacitor and hence, the amount of energy stored in the device. This allows us to use capacitors to store and release energy in various applications, such as in filtering circuits, audio amplifiers, and voltage regulators