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In an AC circuit with only an inductor what will an increase in frequency do?
Inductor impedance is given by jwL, where w=2*pi*frequency. Therefore as the frequency increases the impedance of the inductor increases, causing a larger current flow and a larger power dissipation across the inductor
Why the current increases upto resenance frequency and decreases there after in a series LCR circuit?
At resonance, the L and C impedance cancels out, so the current can be calculated based on the resistance and applied voltage. Imagine increasing frequency of the supply from 0 Hz to very high. At low frequency, the impedance of the inductor is ~0 (defined as Zl = w*L*j), and the impedance of the capacitor is very large (defined as Zc = 1 / (w*C*j)). As you increase the frequency, the impedance of the capacitor will decrease, as the impedance of the inductor increases. At some point (the resonant frequency), these two will be equal, with opposite signs. After crossing the resonant frequency, the inductor impedance will continue growing larger than the capacitor impedance until the total impedance approaches infinite.
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.
Why emitter follower preferred to transforms as a impedance matching?
because it has high input impedance and low output impedance
What is the impedance of a series circuit containing a resistor of 100 ohms and an inductor with an Xl equal to 80 ohms?
a bowl of cereal
What does an electrical choke do?
A choke is an inductor. The impedance of an inductor is dependent on the frequency of the current flowing through it. The greater the frequency, the higher the impedance. Therefore an inductor when used as a choke blocks the flow of high frequency current (by presenting a high impedance), while allowing low frequency or direct current to flow through it. Its function is to block ("choke") high frequencies while passing low frequencies.
Why a coil of wire placaed in series circuit allows low frequency current but not high frequency current to pass?
The opposition to an alternating current offered by a coil, or inductor, is called impedance (symbol Z, measured in ohms) which, in turn, is made up of two components: resistance (symbol R) and inductive reactance (symbol XL). These three quantities are related as follows: Z2 = R2 + XL2.The resistance of an inductor is a fixed value which depends upon the length of the coil's wire, the cross-sectional area of the wire, and the resistivity of the material from which the wire is made.The inductive reactance of an inductor, on the other hand is directly proportional to the frequency of the supply. So, at high frequencies, an inductor's inductive reactance is very much higher than at low frequencies.So, at high frequencies, the impedance of the inductor is higher because its inductive reactance is higher.The current flowing through a coil is, by Ohm's Law: I = V / Z. So, at high frequencies, the inductor's impedance will be much higher than at low frequencies, which means that a very much smaller current will flow when the frequency is high compare to when the frequency is low.
In an AC circuit with only an inductor what will an increase in frequency do?
Inductor impedance is given by jwL, where w=2*pi*frequency. Therefore as the frequency increases the impedance of the inductor increases, causing a larger current flow and a larger power dissipation across the inductor
Why does an inductor offer high impedance to ac but very low impedance to dc?
Because an inductor resists a change in current. The equation of an inductor is ...di/dt = V/L... meaning that the rate of change of current is proportional to voltage and inversely proportional to inductance. Solve the differential equation in a sinusoidal forcing function and you get inductive reactance being ...XL = 2 pi f L
How can convert pulse setting DC to continus DC?
We can use an inductor in series with the circuit to minimize pulses or ripples in the D.C. The inductor provide zero impedance for a D.C source, but provide high impedance for a pulsated wave, so it will not allow pulses to pass through it. A high inductance in the circuit provides smooth D.C. On the other hand we can have a capacitor in parallel to the output.
Why the current increases upto resenance frequency and decreases there after in a series LCR circuit?
At resonance, the L and C impedance cancels out, so the current can be calculated based on the resistance and applied voltage. Imagine increasing frequency of the supply from 0 Hz to very high. At low frequency, the impedance of the inductor is ~0 (defined as Zl = w*L*j), and the impedance of the capacitor is very large (defined as Zc = 1 / (w*C*j)). As you increase the frequency, the impedance of the capacitor will decrease, as the impedance of the inductor increases. At some point (the resonant frequency), these two will be equal, with opposite signs. After crossing the resonant frequency, the inductor impedance will continue growing larger than the capacitor impedance until the total impedance approaches infinite.
How component size decreases when frequency decreases?
The impedance of a component (inductor or capacitor) will change with frequency - resistor impedances will not. Inductor impedance - j*w*L Capacitor impedance - 1/(j*w*C) L = inductance, C = capacitance, j = i = imaginary number, w = frequency in radians The actual inductance and capacitance does not change with frequency, only the impedance.
What is working principle of inductor?
A changing current through an inductor induces a voltage into the inductor, the direction of which always opposes the change in that current.So, in a d.c. circuit, an inductor will oppose (not prevent) any rise or fall in current, although the magnitude of that current will be determined by the resistance of that inductor, not by its inductance.In an a.c. circuit, because the current is continuously changing both in magnitude and in direction, it acts to continuously oppose the current due to its inductive reactance. Inductive reactance is proportional to the inductance of the inductor and the frequency of the supply. The vector sum of the inductive reactance of the inductor and the resistance of the inductor, is termed the impedance of the inductor. Inductive reactance, resistance, and impedance are each measured in ohms.
What is the function of the choke?
A choke is an inductor. An inductor resists a change in current, by presenting a higher impedance to high frequency parts of the spectrum. A choke, then, passes DC, but does not pass high frequency AC, such as noise.
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.
An inductor has an inductive reactance of 64ohm's and a wire resistance of 36ohm's what is the impedance of the inductor?
Impedance is a vector sum using the formula Z = square root (XL2 + R2); where Z = impedance, XL = inductive reactance, and R = resistance. Therefor the formula for a circuit where XL = 64ohm's and R = 36ohm's is Z = square root(642 + 322); Z = 71.6ohms.
What has the author L J Herbst written?
L. J. Herbst has written: 'High speed digital electronics' -- subject(s): Digital integrated circuits 'The impedance of the oxide coated cathode at ultra high frequencies and its influence on theenergy balance of oscillators at these frequencies'
