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Can a 12vac coil be operated by 24vdc?
no, in an ac circuit the coil provides impedance but the DC coil needs some resistance to limit the current
Why is there a difference in current in a coil when you apply dc voltage and then AC voltage to it?
A coil has both resistance and inductance. When you apply a d.c. voltage, the opposition to current is the resistance of the coil. When you apply an a.c. voltage, the opposition to current is impedance -the vector-sum of the coil's resistance and its inductive reactance. Inductive reactance is proportional to the inductance of the coil and the frequency of the supply.
Can the same electric bell work on AC as well DC 250v electric supply?
No, the two systems need a different coil resistance.
How does a speaker work in a circuit?
They will either pull in or push out depending on the polarity of the DC voltage and remain stationary. This is a bad idea as the DC resistance of the voice coil is much less than the AC impedance of the voice coil and it is possible to overheat and burn out the voice coil due to the much higher current the DC voltage can produce in the voice coil compared to the AC voltage that would drive the voice coil in normal operation.
Why pmmc used for DC only?
Because in the coil DC current follow easly and pmmc meter is making with coil and AC current is not follow in coil so we used the pmmc only fpr DC current.
Can a 12vac coil be operated by 24vdc?
no, in an ac circuit the coil provides impedance but the DC coil needs some resistance to limit the current
Why is there a difference in current in a coil when you apply dc voltage and then AC voltage to it?
A coil has both resistance and inductance. When you apply a d.c. voltage, the opposition to current is the resistance of the coil. When you apply an a.c. voltage, the opposition to current is impedance -the vector-sum of the coil's resistance and its inductive reactance. Inductive reactance is proportional to the inductance of the coil and the frequency of the supply.
Dc resistance of diode is a static resistance b dynamic resistance c high resistance d zero resistance?
B - Dynamic resistance
Will a dc motor start if its field resistance is high?
Yes, it will still start.
Why doesnt a field coil in a DC shunt motor lead to short ciruit when it is a fact that an INDUCTOR is a short circuit to DC?
Yes, an inductor is a short circuit to dc...that's true....IF the inductor is an ideal one, that is, the inductor has no resistance but has inductance only. Anything in real world, as you know, is not ideal. An inductor is usually made of a copper wire. A copper wire has its own resistance. If an inductor coil is thin and long (i.e. many turns), it will provide an appreciable resistance to DC, and will no longer be a short circuit.
How do you check if your ignition coil is faulty on a 2000 intrigue?
The 3.5 has coil packs over the spark plugs (called a COP - coil over plug). When I changed my plugs a while back, I visually inspected the coil packs for cracks, and tested the coil resistance. If I remember correctly, they measured a few ohms (can't remember how many, something like 10 ohms), and all were identicle, so I assumed they were OK. If a coil is open, it would measure high resistance. It is unlikely a coil will completely short out, but I'd suspect a coil that reads much different from the others using a DC Volt meter.
Can the same electric bell work on AC as well DC 250v electric supply?
No, the two systems need a different coil resistance.
How does a speaker work in a circuit?
They will either pull in or push out depending on the polarity of the DC voltage and remain stationary. This is a bad idea as the DC resistance of the voice coil is much less than the AC impedance of the voice coil and it is possible to overheat and burn out the voice coil due to the much higher current the DC voltage can produce in the voice coil compared to the AC voltage that would drive the voice coil in normal operation.
When dc voltage is supplied to the primary coil of the transformer then the voltage be induced in secondary or not?
The windings of a transformer have both resistance and inductance. When you apply an AC voltage to the primary winding, the opposition to current flow is a combination of resistance and inductive reactance; although the resistance of the winding is relatively low, its inductive reactance is high. The resulting impedance (the vector sum of resistance and inductive reactance) will, therefore, be high and the resulting current will be low.If, on the other hand, you applied a DC voltage to the winding, the only opposition will be the low resistance of the winding. So, if the value of DC voltage is roughly the same as the rated AC voltage, a large value of current would result -high enough to probably burn out the winding.Since transformers work on the principle of mutual induction, a fluctuating magnetic field is necessary to induce a voltage into the secondary winding. Since a fluctuating magnetic field requires a fluctuating current, a transformer will only work if an AC voltage is applied to its primary winding.So, not only will a transformer not work when a DC voltage is applied to its primary winding, it will probably burn out the primary winding.
What resistance is needed to reduce 5V dc to 4V dc?
The resistance needed is1/(the current flowing through the resistance) ohms.
Why pmmc used for DC only?
Because in the coil DC current follow easly and pmmc meter is making with coil and AC current is not follow in coil so we used the pmmc only fpr DC current.
What resistance is needed to reduce 5V DC to 3V DC?
12v dc to 3v dc
