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Why maximum power is transferred when impedance of source and load is same?
Wiki User
∙ 8y ago
Note that this is about maximum power transfer, NOT about maximum efficiency.The source resistance is assumed to be constant; the load resistant variable.
If you know about calculus, you can derive the maximum power transferred by writing an expression for the power as a function of the variable load. You need no advanced calculus for this - just derivatives, which are used to get the maximum or minimum of a function (as well as high school algebra, of course). You can find the derivation (for the simplified case of a purely resistive circuit) in the Wikipedia article on "Maximum power transfer theorem", as well as a link to the more general case.
Wiki User
∙ 8y ago
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What load impedance Z will result in maximum power transfer from an electric source with an internal impedance of r?
For maximum power transfer, source resistance should match load resistance and source reactance should match load reactance with the opposite sign (so if the load is capacitive, the source should be inductive).
Does the maximum power transfer condition states maximum efficiency condition?
Answer Pmax=E^2/(4xRs) The maximum power is transferred when the load impedance is the complex conjugate of the source impedance. For a dc circuit or a purely resistive circuit, the load resistance equals the source resistance.
What are the importance of impedance matching in amplifiers?
Two reasons. 1...When impedance of source and destination match, power transfer is maximum. 2...If a long transmission line is involved, the characteristic impedance of the line must match the destination impedance, or reflections will occur on the line.
What should be real and reactive power flow through the transmission line when the sending end and receiving end voltages are of same magnitudes and phase angles?
The power transfer equation is this:P = V1*V2*sin(phi)/Xt,V1 = source 1 voltageV2 = source 2 voltagephi = angle between the two sourcesXt = transfer impedance, the impedance of the line + both source impedancesFrom this you can see that if the angle between the two sources is 0, then the power transferred would be zero as well.Reactive power flow *should* be zero if perfectly matched as well, although there will be a small amount of reactive power usage due to line charging (charging current).
What are practical applications of a transformer coupled amplifier?
Well the purpose of the transformer in an amplifier is impedance matching. Lets say the transformer is on the input of a audio amp. Now the amp circuitry has an input impedance (this is important because matching the impedance gives us maximum power transferred from the input signal source to the amp circuit, and that increases performance) and a microphone has an output impedance. So if the microphone is 10,000 ohms and the amp circuit is 500 ohms then the transformer is designed to transform 10,000 ohms to 500 ohms for better signal transfer. If the trans former is on the output of an amplifier the trans former transforms the output impedance of the of the power amp circuit to the input impedance of the load. If the output is a speaker (usually 8 ohms ) and the output impedance of the amp circuit is 1000 ohms then for maximum power transfer the transformer trans forms 1000 ohms to 8 ohms. This was the case using electron tubes. Now with transistors, amplifier circuits can be built with lower output impedances (common collector circuit in a class B power amp) so the costly transformer can be eliminated. Also Audio transformers are made slightly different in design than power transformers. Ausio transformers are designed with higher resistance in the windings to enable a wider frequency response where as power transformers are designed with much lower resistance to keep heating minimized while passing only one power frequency (60 hertz) at large amounts of power. Roger nsc@psu.edu
What will happen in case of AC circuit for maximum power transfer theorem?
According to maximum power transfer theorem for ac circuits maximum power is transferred from source to load when the load resistance is equal to the magnitude of source impedance. The source imoedance is the thevenin equivalent impedance across the load
What load impedance Z will result in maximum power transfer from an electric source with an internal impedance of r?
For maximum power transfer, source resistance should match load resistance and source reactance should match load reactance with the opposite sign (so if the load is capacitive, the source should be inductive).
Does the maximum power transfer condition states maximum efficiency condition?
Answer Pmax=E^2/(4xRs) The maximum power is transferred when the load impedance is the complex conjugate of the source impedance. For a dc circuit or a purely resistive circuit, the load resistance equals the source resistance.
Maximum power is transferred from a source to a load when the load resistance is equal to?
A:is equal to the source
What are the importance of impedance matching in amplifiers?
Two reasons. 1...When impedance of source and destination match, power transfer is maximum. 2...If a long transmission line is involved, the characteristic impedance of the line must match the destination impedance, or reflections will occur on the line.
When A voltage sourcehaving a source impedance Z R jX can deliver maximum Average power to a load impedance Z?
the impedence should be complex conjugate of an equivalent impedence of the network when viewed from the terminals of the load. i.e; Z=R-jx
What are the advantages and disadvantages of maximum power transfer theorem?
The Maximum Power Transfer Theorem is not so much a means of analysis as it is an aid to system design. The maximum amount of power will be dissipated by a load resistance when that load resistance is equal to the Thevenin/Norton resistance of the network supplying the power.
What is the condition for maximum transfer theorem?
For maximum power transfer the load resistance should be equal to the source resistance.An often misunderstood theorem. It applies strictly where one wishes maximum power transfer.It was misused for example in early power systems by trying to match the generator resistance to the load resistance.And it has little application in audio systems, where Power is much less important than Distortion. [for least distortion, the output impedance of the amplifier should be less than 10% of the impedance of the load.]
What are the advantages of Transformer coupling method?
transformer coupling ensures maximum power transfer is obtained even if the output impedance is not equal to the load impedance
What charectristics an electric circuit exhibit under max power transfer condition?
Max power transfer takes place when the total load impedance is equal to the source (power supply) internal impedance.
What is the condition of maximium power transfer of circuit?
Maximum power transfer happens in a circuit when the resistance of the circuit equals the reactance. Impedance Z = R + jX. At R=X, maximum power transfer happens.
What is the powder transfer theorem?
In electrical engineering, the maximum power (transfer) theorem states that, to obtain maximum external power from a source with a finite internal resistance, the resistance of the load must be made the same as that of the source. It is claimed that Moritz von Jacobi was first to discover the maximum power (transfer) theorem which is referred to as "Jacobi's law". The theorem applies to maximum power, and not maximum efficiency. If the resistance of the load is made larger than the resistance of the source, then efficiency is higher, since most of the power is generated in the load, but the overall power is lower since the total circuit resistance goes up. If the internal impedance is made larger than the load then most of the power ends up being dissipated in the source, and although the total power dissipated is higher, due to a lower circuit resistance, it turns out that the amount dissipated in the load is reduced.
