0
The equation of an inductor is ...
di/dt = V/L
... meaning that the rate of change of current in amperes per second is proportional to voltage and inversely proportional to inductance in henries.
If, for example, you connect a 200 millihenry inductor across a 12 volt battery, the current will increase at a rate of 60 amperes per second.
Now, the question is, can the inductor, conductors, and/or battery handle that? The answer is no. Something is going to fail. The inductor will rather quickly look like a short circuit across the battery.
This example does not take resistance into account. Practical inductors, conductors, and batteries have resistance, and that will place an upper limit on current but, still, this is not an appropriate way to connect an inductor to a battery.
DO NOT TRY IT IN THE LAB - THERE IS RISK OF EXPLOSION.
Wiki User
∙ 13y ago
Wiki User
∙ 11y agoWell ideally inductor is meant to block AC by its resistance that is called reactance
(XL =2*pi*f*L). so if it is blocking then where is the energy going. This energy is being stored in magnetic field. As you can see that this energy is later used by tube lights at our homes.
Practicaly:
at low frequency act as a low resistance path so current passes, as it do in our 50 hz system. (no or little blockage of current)
At high frequency act as high resistance path. usually in communication signals where frequencies are very high. here it act as signal blocker.
Wiki User
∙ 10y agoSince DC has zero frequency, hence according to formula X=2*3.14*f(f being frequency), inductance is zero. That is inductor behaves as a short circuit.
Now when DC supply is given across inductor, current is first raised from zero to some value, during this period (change of current fromzero to some value), energy in inductor is stored in form of magneticg field. As soon as DC current reaches to its steady value, inductor is equivalent to short circuit to direct current. No self induced emf is produced and Voltage across inductor is zero.
When inductor is taken out from the circuit, Vl(voltage across inductor) changes its polarity and goes from zero to negative value but Il (current through inductor) maintains the same direction and magnitude. The energy stored in inductor decays through the resistor and voltage Vl rises gradually to zero and current Il drops gradually to zero.
Add your answer:
Earn +20 pts
What happens when a inductor reaches a steady state?
An inductor looks like a piece of wire to DC. It will thus look like a resistor, and inductor properties do not apply.
How dc supply is applied to field coil in a brush less alternator?
Through a coupled inductor, similar to a transformer, but working on DC instead of AC.
Is it possible to heat coil using dc power supply?
Yes, it possible to heat a coil using dc power supply. An inductor resists a change in current, proportional to voltage and inversely proportional to inductance. The equation of an inductor is di/dt = v/L An ideal inductor, if connected to an ideal DC supply, with ideal conductors, would ramp up current in a linear fashion without limit, eventually reaching infinity amperes after infinite time. Since no inductor is ideal, nor is any DC supply, nor is any conductor, the current would reach a maximum based on the capacity of the DC supply and the DC resistance of the inductor and conductors. Since the DC resistance of the inductor is also not zero, this means, by Ohm's law, that the inductor must dissipate some power. That will cause the inductor to heat up.
What happens when dc supply is given to inductor?
The resulting maximum current is limited by the resistance of the inductor. As the current increases from zero to that maximum value, its expanding magnetic field induces a voltage into the inductor which opposes the rise in that current. So, instead of reaching its maximum value instantaneously, it takes some time -determined by the equation:time to maximum current = 5 L / R (seconds)where L = inductance of inductor in henrys, and R = resistance of inductor in ohms.
Can you charge inductor with dc voltage or ac voltage?
Inductors are low pass devices, they conduct most easily at low frequencies. DC is the limiting case for low frequency AC: i.e. DC is the lowest possible AC frequency, zero Hz and thus conducts best through an inductor. Capacitors are high pass devices, they conduct most easily at high frequencies. Infinite frequency AC is the limiting case for high frequency AC. Infinity Hz would conduct best through a capacitor.
What happens when a inductor charges and then discharges?
AnswerWhen you connect DC voltage to an inductor, it opposes the passage of current, which generates a voltage pulse the is several times the value of the applied voltage. When you disconnect the voltage, the electromagnetic field inside the inductor collapses and all the energy it stored is released to the circuit in the form of another large pulse, but this time with opposite polarity.Remember:Inductors oppose changes in current and they store energy in an electromagnetic field.Capacitor oppose changes in voltage and they store energy in an electrostatic field.
What happens when the voltage applied to a dc motor is suddenly reduced to half its value?
cureent becomes high
Why is a high dc voltage applied to a transformer for testing?
A high dc voltage would be applied to test the insulation between the windings.
What happens when a inductor reaches a steady state?
An inductor looks like a piece of wire to DC. It will thus look like a resistor, and inductor properties do not apply.
Will a capacitor lower voltage?
A: As soon as a DC voltage is applied the capacitor is a short or no voltage
Ac voltage applied across a load resistance produce alternating current?
The reason an AC voltage applied across a load resistance produces alternating current is because when you have AC voltage you have to have AC current. If DC voltage is applied, DC current is produced.
How dc supply is applied to field coil in a brush less alternator?
Through a coupled inductor, similar to a transformer, but working on DC instead of AC.
Could an induction type instrument be used to measure a pulsing DC signal of varying voltage?
Yes. As the DC is pulsed or varied in voltage, it will induce a varying magnetic field which can be detected with another inductor.
What type of voltage applied during megger test?
DC
Is it possible to heat coil using dc power supply?
Yes, it possible to heat a coil using dc power supply. An inductor resists a change in current, proportional to voltage and inversely proportional to inductance. The equation of an inductor is di/dt = v/L An ideal inductor, if connected to an ideal DC supply, with ideal conductors, would ramp up current in a linear fashion without limit, eventually reaching infinity amperes after infinite time. Since no inductor is ideal, nor is any DC supply, nor is any conductor, the current would reach a maximum based on the capacity of the DC supply and the DC resistance of the inductor and conductors. Since the DC resistance of the inductor is also not zero, this means, by Ohm's law, that the inductor must dissipate some power. That will cause the inductor to heat up.
How many voltage applied in field winding of dc motor?
110
What happens when dc supply is given to inductor?
The resulting maximum current is limited by the resistance of the inductor. As the current increases from zero to that maximum value, its expanding magnetic field induces a voltage into the inductor which opposes the rise in that current. So, instead of reaching its maximum value instantaneously, it takes some time -determined by the equation:time to maximum current = 5 L / R (seconds)where L = inductance of inductor in henrys, and R = resistance of inductor in ohms.
