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What are the initial conditions for voltage across the capacitor and current through the inductor in the dc steady state?
The initial condition is the voltage and/or current existing at the time a mathematical solution begins. Example: what happens when a resistor is connected across a capacitor? well, you say that at t=0 the resistor is connected, then after that the voltage across the capacitor is v0.exp(-t/RC), where v0 is the starting voltage, t is the time, R is the resistance and C is the capacitance. This simple solution needs only one initial condition which is the starting voltage v0 across the capacitor. Linear differential equations are common in electrical engineering and a complete solution of one (such as the example) always requires one or more initial conditions.
Why the voltage drop across inductance and voltage drop across capacitance is greater than source voltage in series resonance circuit?
The reason for the total voltage drops across the capacitance and inductance IN AN AC CIRCUIT has to do with the different phase angles of the voltages.First, current is the same value and same phase angle everywhere in a series circuit. But, voltage across a capacitor lags current by 90 degrees (capacitor current leads voltage). Next, voltage across a pure inductance leads current by 90 degrees (inductor current lags voltage).The rule that all voltages in a series circuit have to add to the supply voltage still applies, but in this case, the voltage drops are added VECTORALLY, not arithmetically. If you were to graph this addition, you would show any resistance voltage in phase with the current, the capacitor voltage at -90 degrees to the current and the inductor voltage at +90 degrees to the current, for a phase difference between them of 180 degrees, cancelling each other out.In a series resonant circuit, the impedances of the capacitor and inductor cancel each other. The only impedance to the flow of current is any resistance in the circuit. Since real-life inductors always have some resistance, at least there is always some resistance in a series resonant circuit.
What can happen if you use a 440 vac capacitor instead of a 370 vac?
You can always use a higher voltage rated capacitor, it will probably just last a little longer.
How a can capacitor smoothen or reduce the ripple of the voltage produce by the rectifier?
Rectifiers will not give a smooth DC voltage. There are ripples in the voltage given the rectifier. So in order to smoothen the voltage we use capacitor in parallel to the rectifier output. Now lets see how the capacitor smoothen the voltage that is coming from a rectifier...... Capacitor blocks DC and allows AC...... If we take the voltage that is coming from the rectifier it has some ripples in addition to DC, these ripples can be divided in to sinusoidal wave forms ( fictitious )according to the Fourier series. So the rippled DC now divided ( fictitious ) in to a pure DC and sinusoidal AC wave forms having the frequency that is multiples of ripple frequency. Now the DC current will not pass through the capacitor as the capacitor blocks DC. But the AC will pass through it i.e the ripple wave forms that are divided ( fictitious ) in to sinusoidal AC wave forms will pass through the capacitor. So only DC current enters in to the load, which will produce a pure DC voltage drop across the load. In this manner the capacitor smoothens the voltage.
Is mosfet voltage controlled capacitor or inductor?
It's a Field Effect Transistor. I personally wouldn't consider it either of those options; if I had to pick one, it's more inductor-like (in that it has impedance).
What are the initial conditions for voltage across the capacitor and current through the inductor in the dc steady state?
The initial condition is the voltage and/or current existing at the time a mathematical solution begins. Example: what happens when a resistor is connected across a capacitor? well, you say that at t=0 the resistor is connected, then after that the voltage across the capacitor is v0.exp(-t/RC), where v0 is the starting voltage, t is the time, R is the resistance and C is the capacitance. This simple solution needs only one initial condition which is the starting voltage v0 across the capacitor. Linear differential equations are common in electrical engineering and a complete solution of one (such as the example) always requires one or more initial conditions.
What determine the flow of charge through a conductor?
Charges may appear to flow through a capacitor, although in reality they don't.The degree to which charge appears to flow through a capacitor depends on therate at which the voltage across it changes.-- DC voltage doesn't change, so it doesn't appear to pass through a capacitor at all.-- AC voltage is always changing, and the higher its frequency, the more currentit appears to push through a capacitor.
Why the voltage drop across inductance and voltage drop across capacitance is greater than source voltage in series resonance circuit?
The reason for the total voltage drops across the capacitance and inductance IN AN AC CIRCUIT has to do with the different phase angles of the voltages.First, current is the same value and same phase angle everywhere in a series circuit. But, voltage across a capacitor lags current by 90 degrees (capacitor current leads voltage). Next, voltage across a pure inductance leads current by 90 degrees (inductor current lags voltage).The rule that all voltages in a series circuit have to add to the supply voltage still applies, but in this case, the voltage drops are added VECTORALLY, not arithmetically. If you were to graph this addition, you would show any resistance voltage in phase with the current, the capacitor voltage at -90 degrees to the current and the inductor voltage at +90 degrees to the current, for a phase difference between them of 180 degrees, cancelling each other out.In a series resonant circuit, the impedances of the capacitor and inductor cancel each other. The only impedance to the flow of current is any resistance in the circuit. Since real-life inductors always have some resistance, at least there is always some resistance in a series resonant circuit.
What can happen if you use a 440 vac capacitor instead of a 370 vac?
You can always use a higher voltage rated capacitor, it will probably just last a little longer.
How a can capacitor smoothen or reduce the ripple of the voltage produce by the rectifier?
Rectifiers will not give a smooth DC voltage. There are ripples in the voltage given the rectifier. So in order to smoothen the voltage we use capacitor in parallel to the rectifier output. Now lets see how the capacitor smoothen the voltage that is coming from a rectifier...... Capacitor blocks DC and allows AC...... If we take the voltage that is coming from the rectifier it has some ripples in addition to DC, these ripples can be divided in to sinusoidal wave forms ( fictitious )according to the Fourier series. So the rippled DC now divided ( fictitious ) in to a pure DC and sinusoidal AC wave forms having the frequency that is multiples of ripple frequency. Now the DC current will not pass through the capacitor as the capacitor blocks DC. But the AC will pass through it i.e the ripple wave forms that are divided ( fictitious ) in to sinusoidal AC wave forms will pass through the capacitor. So only DC current enters in to the load, which will produce a pure DC voltage drop across the load. In this manner the capacitor smoothens the voltage.
Is a higher capacitance better?
capacitor always opposes the change in voltage , at beginning it shows the initial value and after sum time it charges and shows the maximum valve . Higher capacitor has higher voltage after some time , therefore it damages the equipment.
Is mosfet voltage controlled capacitor or inductor?
It's a Field Effect Transistor. I personally wouldn't consider it either of those options; if I had to pick one, it's more inductor-like (in that it has impedance).
Why is The voltage across the empty socket is equal to the line voltage?
all the sockets are always connected in parallel,due to this the voltage across each soket is same. when any socket is open then there is no voltage loss..so the votage is same like line voltage.
Why does a capacitor block DC and not AC?
A capacitor consists of two plates separated from one another by an insulator. These plates are normally thin foil and can be sandwiched around a very thin insulator and wrapped into a small package. Since there is an insulator between the plates, DC connected to the two plates cannot flow as long as you do not exceed the breakdown voltage of the insulator. AC current is a different story. Because the insulator is very thin and the effective plate area is relatively large, a negative charge building up on one plate causes electrons to be repelled from the opposite plate, and as the charge on the first plate reverses and becomes positive, the electrons in the opposite plate are attracted back again. This results in a matching alternating current flow on the opposite side of the capacitor. actually what happens, capacitor provides a reactance to current. Xc= 1/ (2*pi*f*c) ,where pi=3.14, f=frequency , c=capacitance vaue as dc current is independent of frequency so Xc becomes infinite so dc current gets infinite resistance. so it is blocked
How current leads voltage?
The reason that current leads voltage in a capacitor is rooted in the way a capacitor works. Picture the capacitor. It's basically two conductive plates separated by a short distance and having a dielectric (insulator) between them. Now, let's specify that our cap (capacitor) is completely discharged and we'll hook it up to a DC voltage source through a switch. Flip the switch on and current will begin to flow, but it is important to look at what happens in just the first instant of time. Electrons will begin to accumulate on the negative plate and their presence there will drive electrons off the positive plate. The capacitor is building up a charge. It is developing a voltage across (or between, if you prefer) the plates. But electrons have to begin to pile onto the plate to actually create the difference of potential (voltage) between the plates. The moving electrons (and that's current) that are piling on the plate are already beginning to flow before the voltage is developed between the plates, so current is said to lead voltage in a capacitor. In a capacitor, the current flowing in it depends on the voltage difference across it. On AC, this makes it charge if the voltage is increasing above zero, and discharge if the voltage is reducing towards zero. Because a capacitor has almost no internal resistance, and most loads that it is connected to have only very small resistances in series with the capacitor, the charging and discharging currents depend pretty much on the rate at which the voltage is changing. At the zero crossing point of the sine-wave, when the voltage is actually zero, the rate of change of voltage is very high (the sine-wave is at its steepest), so the current is also very high. If the voltage is positive-going, the current is positive, and if the voltage is negative-going, the current is negative. At the peak of the voltage waveform, the rate of change of voltage is zero or very low (the sine-wave is just about flat, and not really changing its voltage) so the current is zero, too. Since the maximum positive current occurs when the voltage is passing through zero, going positive, and the maximum negative current happens when the voltage is passing through zero, going negative, the current peaks happen 90 degrees before the voltage peaks, so the current is said to lead the voltage. This is the same as saying the voltage lags the current by 90 degrees.
The electric device which blocks DC but allows AC is called?
A capacitor is a device which blocks DC, but allows AC. When a capacitor is completely charged it does not allow current to pass through it. Initially when capacitor starts charging it has maximum current which flows and voltage is minimum, during charging current decreases with time and voltage increases. When capacitor is completely charged, it has maximum voltage and minimum current. However the AC has both positive and negative half cycles, during positive half cycle capacitor starts charging but during negative half cycle it discharges, and hence it doesn't get fully charged at AC, and current always flows through it.
What is capacitor polarized?
A polarized capacitor is one which has a polarity, positive on one terminal, negative on the other. This makes it superficially look like a battery. In use, the capacitor has its positive voltage always higher than that on the negative terminal, it matters that this is the case and this gives rise to the term polarized. This sort of capacitor is commonly found in power supply filters.
