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What else can I help you with?
State two rules for the voltage and current in a series circuit?
Kirchoff's voltage law and Kirchoff's current law
The rules of connecting voltmeter and ammeters in the circuit?
Connect ammeter in series and voltmeter in parallel to the circuit
Do the rules of 0hm's lawas learned in dc theory also apply to ac circuits?
Yes, circuit theory works equally well for ac or dc. But ac circuits also allow capacitance and inductance in addition to resistance, and this is allowed for by using complex numbers for the impedance of the components. So if the supply voltage is 100 v and there is a resistor of 4 ohms in series with a perfect inductor with a reactance of 3 ohms across the supply, the total impedance is 4+j3 ohms, so the current is 100/(4+j3) ohms, which is 20 amps but its total description it 16-j12 amps, showing that the current lags the voltage by 36.87 degrees of phase.
Explain the operation npn transistor when used as amplifier.. and explain the basic operation of NPN when used as switch?
The NPN transistor when used as an amplifier is operating in linear mode, and, when operating as a switch, in saturated mode.In the following discussion, base currrent means base-emitter current, while the base is more positive than the emitter, and collector current means collector-emitter current, while the collector is more positive than the emitter. There is base-collector current, but we are going to ignore it for now - besides, we are going to discuss class A, common emitter, configuration.The PNP transistor is very similar. Everything is backwards, including Vcc, which is now -Vcc, or appropriate reconfiguration. The rules are the same - just backward.In switched or saturated mode, the ratio of base to collector current is far greater than beta-dc, or hFe, so the transistor is operating way out of its linear mode. We call that saturated mode, and the transistor is essentially either fully on or fully off, and therefore operating as an on-off switch.The rest of this discussion will focus on linear or amplilfier mode.If the ratio of base to collector current is less than beta-dc, or hFe and, if both base and collector voltage are greater than cutoff voltage, then the transistor is operating in linear mode. Well, sort of, for best linear mode, we look at the data sheet, or make empirical observations, and we pick the base and collector currents that are centered between the base knee and the collector knee, i.e. "in the middle of" the linear region.In this mode, a very small base current can control a much larger collector current, and, most importantly, a very small change in base current can create a much larger change in collector current.In the theoretical case, for example, where the emitter is grounded and where hFe is 100, then 1 mA of base current translates to 100 mA of collector current, and 2 mA of base current translates to 200 mA of collector current. Problem is, that hFe varies amongst even so called identical transistors, and hFe varies as a function of temperature as well.So, in the practical case, an emitter resistor is added to stabilize the transistor and place limits on the need for hFe of a particular value. Done properly, this will yield predictable gain for various transistors and for various temperatures.Now, lets look at how gain works in the practical sense. The base voltage is also a known delta above emitter voltage. Yes, temperature will affect this, but proper design can make this a negligable factor. The emitter current times the emitter voltage results in a known voltage. By Norton's current law, the base current and the collector current add up to be the emitter current, but by hFe, the base current is very much smaller than collector current, meaning that the really important part is that collector and emitter current are the same for all practical purposes.So, now add a collector resistor. Ignoring base current, the collector/emitter circuit is a series circuit, and Norton's current law, reinterpreted for series circuits, says the two resistors have the same current. Think about what that means; if the current in both resistors is the same, then the ratio of the voltage across the two resistors is proportional to their value. The gain of the amplifier is collector resistor divided by emitter resistor. That is critical knowledge. Again, base current enters into the equation but, if hFe is high enough, it does not matter.All that is left, then, is to bias the base. You want to pick a base voltage (current) that places the collector current in the center (or in an appropriate point) of the linear region. Choose a nominal hFe, divide by collector current, and you get an approximation of what base current bias should be. Choose a resistor divider to match, keeping in mind that the two resistors (base to Vcc and base to Gnd) in parallel will reflect your effective input impedance.Review everything, particularly your power levels. To calculate the power through the collector/emitter junction subtract collector resistor voltage from emitter resistor voltage from Vcc, and you get collector/emitter voltage. Multiply that by collector current, and you get power dissipated by the transistor in nomial bias condition.Play with the values until you have what you want. You could even set this up in a spreadsheet.Last, but not least, there is a base bias voltage. If you are going to amplify something, you need to maintain that nominal bias voltage. Connect a series capacitor between the base and the input point and you will be able to operate from an AC signal that is zero referenced. Just pick the RC time constant appropropriate for your application.Similarly, there is a collector bias, so, if you want an AC output zero referenced, use a series capacitor also in between the collector and the ouput.This is an AC coupled, inverting amplifier. There are DC coupled non-inverting versions, but they are more complicated, requiring more than one transistor, and this answer does not address them. Good luck!
How do you convert a low-voltage outside lamp post to 110v?
This type of conversion could be troublesome. To change to 120 volt system means that the feed wire has to be rated for underground use and rated at 300 volts. Where as the existing low voltage wiring does not have to be subjected to these rules due to using low voltage. The lamp socket in the post is next. It has to be rated at 120 volts and the existing low voltage socket can not be used.
What are the 2 rules for the voltage and current in a series circuit?
In a series circuit, the current remains constant throughout the circuit. The voltage across each component in a series circuit adds up to the total voltage of the circuit.
What are the two rules for the voltage and current in a series circuit?
1) At every point in the circuit, the current is the same. 2) The sum of the voltage drops across each component is zero.
What is the rules of voltage in parallel circuits?
In parallel circuits, the voltage across each branch is the same as the total voltage of the circuit. This is because each branch is connected directly across the voltage source. This rule is known as Kirchhoff's voltage law.
State two rules for the voltage and current in a series circuit?
Kirchoff's voltage law and Kirchoff's current law
What are the laws governing parallel circuit?
Well, this is a nice question. I will just try to answer it. Note that the combined resistance in parallel will always be less than any of the individual resistances. In the parallel system, there is a separate independent path from the source to each resistance and back to the source, therefore each has the same voltage drop. This means that the voltage must be the same at each point in the parallel circuits. There are three rules governing simple parallel circuits of resistive elements: 1. Voltage across each resistor is the same as the voltage across the parallel combination. 2. The current flowing through the parallel combination is the sum of the current in the separate branches. 3. Summing resistance of a parallel circuit can be stated as follows: The reciprocal of the total resistance is equal to the sum of the reciprocals of each of the individual resistances. So that you can have more information about series and parallel circuits, just try to visit the website....: http://elpaso.apogee.net/foe/fcsppr.asp
What are three rules of electricity?
Current flows from higher voltage to lower voltage. The total current entering a junction must equal the total current leaving the junction. Resistance in a circuit reduces the flow of current.
What are the rules in series circuit?
Kirchoff's Current Law: The current at every point in a series circuit is the same. This can also be expressed as the sum of the currents entering a node is zero. Kirchoff's Voltage Law: The sum of the voltage drops across all elements in a series circuit add up to zero.
How are parallel circuits and series circuits alike?
in parallel the voltage stays the same in parallell the current is shared in series the voltage is shared in series the current stays the same the main similarity between parallel and series circuits is when voltage increases, current increases.
What is example of dependent source and independent source of voltage and current?
Boss its a circuit not a device, you can also create one of yours..... just use simple logic of voltage divider and current divider rules...-satendra.svnit@gmail.com
Which is the best describes a parallel circuit?
A parallel circuit has more than one resistor (anything that uses electricity to do work) and gets its name from having multiple (parallel) paths to move along . Charges can move through any of several paths. If one of the items in the circuit is broken then no charge will move through that path, but other paths will continue to have charges flow through them. Parallel circuits are found in most household electrical wiring. This is done so that lights don't stop working just because you turned your TV off.Below is an animation of a parallel circuit where electrical energy is shown as gravitational potential energy (GPE). The greater the change in height, the more energy is used or the more work is done.The following rules apply to a parallel circuit:The potential drops of each branch equals the potential rise of the source.The total current is equal to the sum of the currents in the branches.The inverse of the total resistance of the circuit (also called effective resistance) is equal to the sum of the inverses of the individual resistances. One important thing to notice from this last equation is that the more branches you add to a parallel circuit (the more things you plug in) the lower the total resistance becomes. Remember that as the total resistance decreases, the total current increases. So, the more things you plug in, the more current has to flow through the wiring in the wall. That's why plugging too many things in to one electrical outlet can create a real fire hazard.
The rules of connecting voltmeter and ammeters in the circuit?
Connect ammeter in series and voltmeter in parallel to the circuit
What are the series circuit rules?
current is constant in the series circuit. The resistances of the components add up and the potential differences is divided propotionally over the components depending on their resistances.
