0
Add your answer:
Earn +20 pts
What happens to the current in a circuit as a capacitor charges?
What happens to the current in a circuit as a capacitor charges depends on the circuit. As a capacitor charges, the voltage drop across it increases. In a typical circuit with a constant voltage source and a resistor charging the capacitor, then the current in the circuit will decrease logarithmically over time as the capacitor charges, with the end result that the current is zero, and the voltage across the capacitor is the same as the voltage source.
Why voltage leads current in a inductor?
An inductor opposes current changes. In AC circuit, this opposition is observed as a lag in the current waveform.
What is the var meter?
A VAR Meter is used to measure Reactive Power in AC Circuits - Pure reactive components dissipate zero power, which makes sense in a DC circuit, as a capacitor passes no DC current and an inductor displaces no voltage. Yet, in an AC circuit, the reactive components "seem" to dissipate power, as current passes through the capacitor and the inductor sees a voltage drop. This counterfeit power is called "reactive power" and is measured not in Watts, but in VARs (Volt-Amps-Reactive). Its mathematical formula symbol is "Q". A VAR Meter is used to measure Reactive Power in AC Circuits - Pure reactive components dissipate zero power, which makes sense in a DC circuit, as a capacitor passes no DC current and an inductor displaces no voltage. Yet, in an AC circuit, the reactive components "seem" to dissipate power, as current passes through the capacitor and the inductor sees a voltage drop. This counterfeit power is called "reactive power" and is measured not in Watts, but in VARs (Volt-Amps-Reactive). Its mathematical formula symbol is "Q".
Why capacitor in transistor amplifier circuit at input?
Because capacitor not allow to pass dc voltage,but capacitor allow ac voltage and signal.Purpose is to block dc voltage.That is coupling condenser.
What will happen if two terminals of capacitor are shorted?
When the terminals of a capacitor are connected together, the capacitor will discharge, returning to a zero potential state. Capacitors resist voltage change, meaning that if the capacitor is in a circuit that has zero voltage potential, the capacitor will eventually achieve zero potential. If the capacitor is in a circuit that has a 5 volt potential, the capacitor will seek and attempt to maintain that 5 volt potential (provided that the capacitor is rated at 5 volts or more). In an AC circuit, the capacitor will tend to smooth out the sin wave of the current, resisting change in both directions. In a DC power supply circuit, a capacitor will tend to reduce the voltage "ripple", and if the circuit is designed properly, will provide a smooth DC voltage. Shorting the terminals of a capacitor is effectively what often happens in many circuits; it's not a problem.
What is the difference between an inductor and a capacitor?
A capacitor appears as a short circuit to AC. An Inductor appears as a short circit to DC. Capacitor stores electrical energy in the form of Voltage, E= 1/2CV2 , Where as an Inductor stores Electrical energy in terms of current, E = 1/2LI2. 1. Capacitor stores an electric field, whereas inductor stores a magnetic field. 2. Capacitor is open circuit for DC, and inductor is short circuit for DC. 3. In an AC circuit, for capacitor, voltage 'lags' current, whereas for inductor, current 'lags' voltage. 4. Energy stored in a capacitor is calculated in terms of voltage (1/2 x CV2), and this is done in terms of current for inductor (1/2 x LI2) Electrikals...
Why does the current lead the voltage across a capacitor by 90 degree rather than lag it?
Because the capacitor resists a change in voltage, while an inductor resists a change in current. This causes current to lead voltage in an AC circuit with a capacitor, while current would lag voltage in an AC circuit with an inductor.
Is mosfet voltage controlled capacitor or inductor?
Capacitor
What effect does a capacitor have on an ac voltage?
A mnemonic that was taught in electrical school many years ago is ELI the ICEman. In an inductive circuit, the current through the inductor lags the voltage (E) (L) inductor (I) current.In a capacitive circuit, the voltage through the capacitor lags the current (I) (C)capacitor (E) voltage.See related links below.
Why inductor use in series capacitor in parallel?
That depends on the type of circuit you are talking about. Sometimes both an inductor and capacitor are both in parallel with each other. This is called a tank circuit. Sometimes they are both used in series. These are both examples of resonant circuits. Sometimes the inductor can be in parallel with an applied voltage and the capacitor in series. This is a form of high pass filter. On the other hand, the inductor can be in series and the capacitor in parallel to for a low pass filter.
What is difference between capacitor and inductor?
Inductor stores the energy in the form magnetic flux, but the capacitor stores the energy in the form of electric charges.In the inductor voltage leads the current, where as in the capacitor current leads the voltage.
What is the advantage of capacitor filter over inductor filter?
this is because capacitor filter is sparking in high voltage where as inductor filter will not sparking.
What is the significance of using capacitor in AC circuit?
A capacitor is included in the circuit to act as a filter to reduce ripple voltage. ... filter circuitmay be built using two capacitors and an inductor: ...look at http://en.wikipedia.org/wiki/Reservoir_capacitor
What is single tuned voltage amplifier?
it is a circuit consisting of a tuned circuit with a capacitor in parallel with inductor and it is connected to collector terminal in common emitter configuration,, and it is used as frequency receiver
How the capacitor removes the ripples from the rectified voltage?
During the AC cycle, the capacitor charges when the rectifier conducts, and maintains the voltage when the rectifier is not conducting.
How do you find whether it is inductor or capacitor if only power factor is given?
in case of inductor or capacitor power factor is always zero.as power factor is cosine of phase angle between voltage and current. in case of inductor and capacitor phase angle between voltage and current is 90 so it become zero so if given power factor is zero then it can be inductor or capacitor.
What is difference among resistor capacitor and inductor?
In an AC circuit through a resistor the voltage and current are said to be in phase. Ie on the oscilloscope in the sine wave as the voltage rises so does the current in tandem. Through an inductor an electromagnetic field is created in the coil which produces a back emf which acts against any change in voltage. This slows down any sharp change in voltage as when a circuit is energised. With an inductor the voltage and current are out of phase. The voltage is said to lead over the current. It is displaced by 90 degrees. It is ahead of the current by 90 degrees on the sine wave. Through a capacitor the current rises until it is fully charged and then no more current flows. An AC current is constantly changing direction at 50 Hz in the UK. Through a capacitor the current leads over the voltage by 90 degrees in the sine wave. A capacitor can balance out the effect of the inductor. The inductor decreases the power factor, the capacitor increases the power factor. With an inductor a circuit draws more current, with a capacitor the current draw decreases. P=IxVxPf. Where Pf is the power factor or power correction factor. Factories will have a big capacitor to correct the power factor for induction motors. This improves the electrical efficiency and lowers the electric bill!
