If a capacitor blocks dc voltage (after charged), then what is the point of a capacitor in dc applictions?

Answer 1

Depends where it is used. In the power supply, it is used as a filter to mainly smooth the DC level. But in a DC application, a capacitor, in junction with a resistor, is used to provide timing (delay) dictated by the value of both components. It has other functions. Think of it as a very fast chargable battery - it does maintain a DC charge.

Answer 2

truthfully a capacitor will charge to the DC voltage in a circuit and in a ability grant will grant modern-day to the burden while the rectifier diode(s) are reversed biased. Capacitors: a) shop capability, the capability in joules = (a million/2)C(V^2) the place C is the capacitance and V is the voltage b) have an impedance Xc in ohms = a million/(2 pi(f)(C)) this impedance is infinite at DC and gets decrease in fee because of the fact the frequency f get larger. DC can't bypass by way of them.

Answer 3

The only uses of capacitors in DC applications that I can think of are for smoothing and getting rid of voltage spikes. Say you want a steady low voltage supply. You transform down the mains voltage to the low voltage you want. Then you use a full-wave rectifier. But the output from this is bumpy. So you feed it into a smoothing circuit consisting of a network of capacitors and inductors. Finally you've got something that looks like the output from a battery that you can use to power ICs.

Answer 4

It is true that a capacitor blocks the flow of current after it is charged, which is why in real-life circuits, capacitors are connected in parallel to the circuit so that it does not restrict the normal operation of the circuit. The purpose of having the capacitor is that DC voltage has ripples (fluctuations) in it. Having a charged capacitor connected in parallel to a circuit smoothens ripples. (Ripples are undesirable and are bad for many electronic components) Capacitors are also used for a smooth discharge: for example, in many modern devices like cell phones, lights tend to fade out than just turn off abruptly. This is achieved using a capacitor.

Answer 5

timing.

capacitors are used in simple flip-flop style circuits.
gates have three nodes, an in , an out, and a gate sensor.

the gate sensor acts upon either voltage or amperage, depending on the type. when placed in series with a capacitor, this may be used to time the opening or closing of the gate circuit.

if we know the charge time of a capacator at a specific voltage, then we can control the timing of a second circuit.

if the gate is set to open at 0 volts, then it will stay closed, and the second circuit will remain continuous, until the capacitor fully carges. when charge is reached, the capacitor acts as an open, and the gate detects 0 volts. the gate then causes an open in the secondary circuit and timing is achieved.

that's just one example. there are many others.

Answer 6

It's also used as an energy storage device. When a circuit suddenly needs a big dose of current, say a car sub-woofer amp, a capacitor can quickly provide surge current for that big "THUMP". They're also used to hold up memory in case of a power failure in place of batteries.

Answer 7

If you put a resister in series with the cap. you could control how long it takes to charge. If you then had a relay in parallel with the cap. you could contol when that relay energizes.....Say you wanted a motor to start five seconds after you hit the start button. This relatively simple circuit could accomplish this.

Answer 8

remove ripples making the DC steady Its a filter