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In a multistage amplifier input impedance is high and output impedance is low justify the statement?
no. input impedance is low & output impedance is high
What is the need of impedance matching?
Impedance matching is setting the input impedance (load) equal to the fixed output impedance (source) to which it is connected, in order to maximize the power transfer.Matching is obtained when Zload = Zsource.In audio and sound engineering we have really no impedance matching. There is only impedance bridging. Zload >> Zsource.Scroll down to related links and look at "Impedance bridging - Wikipedia".
Why is impedance matching used in electronics?
Impedance matching is used in electronics to get an electronic device with an input and output source to work. Impedance matching will give the electronic it's maximum transfer of voltage. An example of this are FM radio receivers.
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.
Why capacitor reduce gain of ce amplifier?
Where is this capacitor in the circuit?A capacitor across the emitter bias resistor actually increases the AC gain because it bypasses that resistor, by increasing the ratio of collector impedance to emitter impedance which determines the amplifier voltage gain.A capacitor across the base input resistor actually increases the AC gain because it bypasses that resistor, by decreasing the attenuation of the input signal by the input circuit network.
What is Intrinsic Impedance?
intrinsic impedance is ratio of E/H from a uniform plane ve in a materal
What is characteristics impedance?
The characteristic impedance or surge impedance belongs to a uniform transmission line, usually written Z0. It is the ratio of the amplitudes of a single pair of voltage and current waves propagating along the line in the absence of reflections.
What is x r ratio?
x/r ratio is reactance/resistance where reactance is impedance * frequency (60 hz)
How do you make an impedance- and level-matching transformer?
You'll need to decide *which* one you want. An impedance-matching transformer has a defined primary-to-secondary turns ratio. This *may* give the level match that you want, it may not. Alternately, you can design for a level match, which also *may* give the impedance ratio you want, it may not. It also has a defined turns ratio, but this may not meet an impedance-matching requirement. For impedance matching find the ratio of impedances, take its square root, and use that as the turns ratio: 2400 ohms to 600 ohms has an impedance ratio of 4:1, so its turns ratio will be (sqrt4) = 2:1. To level-shift 1.23 volts (+4 dB) to 300 mV (-10 dB), the ratio is (1.23/0.3) approx 4:1. From the above, you could match 2400 ohms to 600 ohms, but *not* +4 dB to -10 dB with the one transformer.
When a generator of internal impedance and operating at 1gigahertz feeds a load via a coaxial line of characteristic impedance 50 ohm then the voltage wave ratio on the feed line is?
For a voltage standing wave ratio (VSWR) of 1.0, the source impedance, load impedance, and transmission line characteristic impedance must be matched. To calculate actual VSWR, you need to know these three values. You're question only supplies one (50 ohm line). Review wikipedia's writeup on "standing wave ratio" to glean an understanding of what you're asking about.
What is the output impedance of a constant voltage source and constant current source?
The output impedance is z= V/I, the ratio of the constant voltage and the constant current source.
What is synchronous impedance?
Synchronous impedance is also known as the EMF method. It is a ratio of open circuits to short circuits, when they both are referred to the same field excitation.
What are the characteristics of instrumentation amplifier?
a high common mode rejection ratio, high impedance
What is the ratio of apparent power to true power?
The ratio of apparent power to true power is called 'admittance', expressed in siemens. Admittance is the inverse of impedance.
In a pentode power amplifier the effective impedance of the load is 600 ohms The signal current varies between 50 and 200 ma The effective voltage across the secondary of the transformer is 10.6 volts?
It might be. Or it might not. You need to specify the transformer's turns ratio or its impedance ratio, and th eload on the secondary.
Why do you expect an infinity line to have an input impedance equal to the caractarictic impedance?
The characteristic impedance of a transmission line is the ratio of voltage to current of the propagating electrical wave. The line input impedance is the result of the superposition of forward and reverse, or reflected waves when the terminating impedance is not adapted. If the line is infinite, nothing returns from its end and only the forward wave exits. The voltage to current ratio is then the line characteristic impedance. Remark that the same occurs when the line is terminated by its characteristic impedance, the forward wave finds a perfect continuity to the load and no energy is reflected back to the line. A matched line is like an infinite line when looked from the input terminals. Long real lossy lines also act as infinite lines for the energy of the reflected wave is dissipated along the line before reaching the source.
Which is better high input impedance or low input impedance and why?
That depends on the output impedance. In electronic we use voltage bridging, that is a relative low output impedance to a higher input impedance. Usualy the input impedance is more than ten times higher then the output impedance. An input impedance is called also a load impedance or an external impedance. An output impedance is called also a source impedance or an internal impedance.
