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Transistors are typically operated in one of two (well, four) regions: saturation/cutoff or linear (forward or reverse).
When used as amplifiers, transistors are operated in the linear region. If you look at a transistor's V-I (voltage - current) characteristic, you'll see the linear region is somewhere "in the middle", where there is sufficient voltage applied (so current flows), but not to much (so the transistor is not saturated). To get transistors to operate in this middle region, DC circuits are used to bias the transistor to the center of the linear region. So the transistor is working on both AC (the signal applied to the input that is amplified at the output) and DC (the biasing network to allow the transistor to operate as a linear amplifier).
When used in saturation/cutoff, the transistor is being used as a switch (on/off). this is common in logic devices (gates, arrays, CPUs, etc.). The input to these devices is typically an irregular AC wave (a square wave of information). A power source is needed that is DC, however, to provide the power to drive the output to one state or the other.
So proper transistor operation requires both AC (as the signal) and DC (as the biasing network, or power source).
Diode is a device which allows the current through it, when we apply above the break down voltage on it. which means 0.7v for silicon diode. and 0.3 volt for germanium diode.
here if we apply ac voltage on diode, it will pass only the +ve half cycle of ac. it will block only the negative half cycle of ac.
I mean diode allows only the partial current of ac.
yes, it can convert a.c to d.c, cause a transister has diodes inside them. u just has to figure out the anode and cathode.
transistors work on dc not ac however they can have ac signalss fed into them
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Can an ac amplifier amplify the DC signals?
An amplifier generally amplifies an AC waveform (such as sound), and is powered by a DC source. The majority of the power at the output is then coming from a DC source (the power supply in a power amplifier will convert the 50/60Hz AC power in to DC for the amplifier circuitry). So you can make the argument the above (question) is a true statement. But an amplifier wouldn't be used to convert from DC to AC power (in general).
How does auto transformer work with DC supply?
Transformers don't work with DC supplies - they only work on AC.
Does electrical transformer use a DC or AC source?
A transformer is a device to convert high voltage AC to low voltage AC & vice-versa. It works on the principle of induction. Since induction occurs only in an AC supply, a transformer cannot work on DC.. So, it is not possible to convert DC supply to AC using transformer. You would need an inverter to convert DC to AC.
Why you use capacitor before connecting transtitor?
Before connecting to the transistor we use a capacitor becausefor the transistor to amplify we should first apply DC biasing so that we can set an operating point to itso once the transistor is biased DC currents flow in the whole circuitryAll the AC signal source are shorts to the DC currents so we employ capacitor for two reasons1.As capacitor blocks DC and allows AC it is connected for not moving the DC operating point of the transistor and making it fixed since if any small DC part arises in the signal it leads to the change of operating point and our amplification procees gets affected2.To block the already present DC currents in the circuitry for not getting away and making it fixed
Why do you still use both ac and DC?
Because some appliances work with ac current and some with dc current.
What is the ac equivalent circuit for a transistor?
Transistor are DC output, Triac are AC output.
Can DC series motor work on ac and DC and why?
A dc series motor can work on dc and ac because dc motors are totally reversible.
How transistor works in ac?
work like on off switch!!
Is it true a transistor changes alternating current into direct current?
No, a transistor does not change alternating current into direct current. A transistor can amplify or switch electrical signals, but it does not convert between AC and DC. Rectifiers are typically used for converting AC to DC.
How does DC to ac power supply work?
If having DC and AC is required then a PWM pulse width modulator is required to chop the DC to make AC
Do laptop work on ac or DC and how?
A laptop runs on DC. Either from the battery, or the external power supply, which converts AC power to DC.
Can a dc motor work in ac?
No it cant
Can an ac amplifier amplify the DC signals?
An amplifier generally amplifies an AC waveform (such as sound), and is powered by a DC source. The majority of the power at the output is then coming from a DC source (the power supply in a power amplifier will convert the 50/60Hz AC power in to DC for the amplifier circuitry). So you can make the argument the above (question) is a true statement. But an amplifier wouldn't be used to convert from DC to AC power (in general).
How does auto transformer work with DC supply?
Transformers don't work with DC supplies - they only work on AC.
What is meant by saying at what current is transistor biased?
The saying "at what current is transistor biased" means to ask the current through the transistor when there is no signal present. Typically, a transistor is biased at the center of its linear region, so as to minimize distortion. This, of course, depends on whether or not the transistor is AC or DC coupled, and where the clipping points might be.
Does electrical transformer use a DC or AC source?
A transformer is a device to convert high voltage AC to low voltage AC & vice-versa. It works on the principle of induction. Since induction occurs only in an AC supply, a transformer cannot work on DC.. So, it is not possible to convert DC supply to AC using transformer. You would need an inverter to convert DC to AC.
Why you use capacitor before connecting transtitor?
Before connecting to the transistor we use a capacitor becausefor the transistor to amplify we should first apply DC biasing so that we can set an operating point to itso once the transistor is biased DC currents flow in the whole circuitryAll the AC signal source are shorts to the DC currents so we employ capacitor for two reasons1.As capacitor blocks DC and allows AC it is connected for not moving the DC operating point of the transistor and making it fixed since if any small DC part arises in the signal it leads to the change of operating point and our amplification procees gets affected2.To block the already present DC currents in the circuitry for not getting away and making it fixed
