could someone explain exactly what a capacitor does in a circuit?

Answer 1

There are three main functions of capacitors:

1. they let AC signals through while stopping DC
2. they store electrons, allowing ripples to be smoothed out of rectified DC voltages.
3. in parallel with an inductance, they form a tuned circuit which resonates at a particular frequency. This is used in radios to tune into a particular frequency of carrier wave.

Capacitors designed for function 2 are normally much bigger than those for function 1. Capacitors for function 3 are normally variable ones.

Answer 2

That is a very variable question. Capacitors do store electrical charges. They store electrons in a power supply circuit so that during the non-charging time in the operation of the rectifiers, the store electrons flow to the circuit using them. Capacitors give an inherent 90 degree shift to an alternating voltage. This is why they are used in split phase motors. They shift the applied voltage by about 90 degrees, giving the magnetic difference to cause the motor to be gin to spin. This phase shift is also used in oscillators. A capacitor also produces an impedance, or a "dynamic" resistance to AC voltages, and currents. This is used in tuned circuits to create circuits that pass or impede the passage of certain signals. In a series circuit, with an inductor (coil) the desired frequency is sent to ground, and out of the operation of the device, or to a different part of the device for other device functions, such as in a mixer in a radio. There are a lot of uses for a capacitor, far more than can be covered here.

Answer 3

A capacitor stores an electric charge between two conductive plates seperated by an insulator. The purpose of this is to provide a charge when the voltage at the positive terminal drops below the charge level of the capacitor. Capacitors block DC current, while allowing AC to pass through(frequency and cap value dependant). So caps can either filter(decouple), or block(couple).

Answer 4

A capacitor is an electronic component which is used in a wide variety of circuit applications due to its ability to store charge.

Capacitors are used in DC circuits to provide "bursts of energy." Typical examples would be a capacitor to jump start a motor or a capacitor used to operate a camera's flash.

When the switch is closed, charges immediately start flowing onto the plates of the capacitor. As the charge on the capacitor's plates increases, this transient current decreases; until finally, the current ceases to flow and the capacitor is fully charged. In the diagram shown below, the right plate of the capacitor would be positively charged and its left plate negatively charged since the plates are arbitrarily assigned as + and - according to their proximity to the nearest battery terminal.

Answer 5

Capacitor is an electric circuit element used to store a charge temporarily. A capacitor usually consists of two metallic plates separated and insulated from each other by a dielectric substance.

Answer 6

basically there are 2 types of capacitors, both normally used on electric motors and possibly on other induction circuits,
1 is a start capacitor which when the motor is switched on will electrically kick start the motor to life, a single phase motor can draw up to 5 times its running current on start-up(without the cap the motor will burn out)
2 is a run capacitor this can be used with a start cap and often is, this cap will ensure electrical contininuity whilst the motor is running.
hope this helps

Answer 7

" ..... In a series circuit, with an inductor (coil) the desired frequency is sent to ground, ..... "

What has "ground" got to do with it?

And "sent to ground" ? What the hell does that mean?

Answer 8

they store electrons (electricity)