1) The main purpose of the capacitor is to store charge . If an instantanous strong current is to be flown in a circuit,the best way would be to connect the terminals of the circuit to a charge capacitor
2 A capacitor can store electric energy when disconnected from its charging circuit, so it can be used like a temporary battery. Capacitors are commonly used in electronic devices to maintain power supply while batteries are being changed. (This prevents loss of information in volatile memory.)
3.Capacitor are used in many electrical intstruments like ignition systems of the motor engines.It is also employed in Electric fan
4.Because capacitors pass AC but block DC signals (when charged up to the applied dc voltage), they are often used to separate the AC and DC components of a signal. This method is known as AC coupling or “capacitive coupling”. Here, a large value of capacitance, whose value need not be accurately controlled, but whose reactance is small at the signal frequency, is employed.
5. Capacitors are also used in Scientic Study.Using plates of different size and shape,different electric field configuration are established between the plates and the behavior of dielectric sunstances placed in these field are studied
6.Groups of large, specially constructed, low-inductance high-voltage capacitors (capacitor banks) are used to supply huge pulses of current for many pulsed power applications. These include electromagnetic forming,pulsed lasers ,pulse forming networks, radar, fusion research, and particle accelerators.