A capacitor is an electrical component that consists of a pair of conductors separated by an insulator. A voltage applied across the conductors creates an electrical field in the capacitor, which stores energy. A capacitor operates like a battery in that, if a potential difference is applied across it that can cause a charge greater than its "present" charge, it will be charged up. Should the opposite happen, the capacitor will release a charge.
Capacitors are fundamentally different from batteries in that batteries continually discharge, whereas capacitors, in a circuit, will continually discharge, then recharge.
Determine what kind of battery to use to pass a potential difference across the capacitor. This depends on the voltage rating of the capacitor; the maximum voltage of the battery used should be equal to the capacitor's voltage rating.
Wire the circuit to charge the capacitor: Connect one end of the battery holder to the switch, which is open in the up position.
Attach a resistor to the other end of the switch. The resistor prevents the capacitor from being charged too quickly.
Connect one end of the capacitor to the resistor and the other end of the capacitor to the battery holder.
Connect the multimeter wiring to both ends of the capacitor and set the multimeter to read "voltage."
Connect the battery to the battery holder and close the switch. View the voltage reading on the multimeter; this is the voltage passing across and charging the capacitor. The capacitor is now charged, like a battery.
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