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Simple addition, but it must be done with complex numbers.

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How do you write out an equation used to find the inductive reactance ant the capacitive reactance?

Xc(capacitive reactance) = 1/(2piFC)XL(inductive reactance) = 2piFLWhere pi=3.14etc.,F=frequency and C and L are capacitance and inductance.Please pardon lack of proper symbology.


Why input impedance should be high for an amplifier?

The best way to answer this question might be to consider the consequences if the input impedance was low: with a low input impedance, (signifficant) current would start flowing, and the amplifier would draw energy from the signal sources. None of the typical signal sources is designed to deliver energy on its outputs (after all, this is where the amplifier itself comes in). It is certainly possible to think that some of these sources might be changed to deliver some energy, but this is not the case with present-time tuners, CD players, microphones, and so forth. Assuming that the energy supply was not the issue, just to ponder this theoretical scenario a little further, the fact that current would flow from the source to the amplifier would also make the signal more vulnerable to the characteristics of the cable that connects the two. The high impedance of an amplifier input draws no energy, thereby avoiding these issues. It is the amplifier's task to convert a very low energy, voltage-driven signal into an higher energy output signal (driving the speakers which themselves have a very low impedance). ---- The way I typically think about this is to consider connecting a load to a Thevenin equivalent circuit [1]. The voltage across the load is given by the voltage divider formula (Vload = Vsrc * Rload/(Rload+Rthevenin)). If there is a very low load impedance--this means the amplifier has a very low input impedance--most of the source voltage will drop over the Thevenin equivalent resistance. With a very high input impedance, however, the majority of the signal voltage will be transferred from the source to the load because in the above equation, if Rload >> Rthevenin, Vload is approximately equal to Vsrc. if an amplifier has low impedance input the f/b must be low impedance also which make it in practical to use. The hi impedance of a typical amplifier is because the input is one two diodes basically operating on it exponential curve. Making it virtual the same as the other diode. for a differential amplifier. Boltzmann constant will define the impedance of a single diode.


When you prove a voltage to be induced using a Simpson why does the input impeadance on the different voltage scales produce different readings for the amount of voltage?

One possibility is that the accuracy of the Simpson is different on the different scales. Another (more probable) possibility is that the impedance of the Simpson on the different scales is sufficiently different so as to affect the reading. This is a common issue with low impedance multi-meters. Lets say you are using a typical Simpson meter with 20,000 Ohms per Volt. On a three volt scale, that means the meter itself has an impedance of 60,000 Ohms. On a 60 volt scale, however the meter has an impedance of 1,200,000 Ohms. Depending on the circuit impedance, that can have a significant impact on the final reading, which must be taken into consideration. Look at the equation for parallel resistance: RT = R1R2 / (R1+R2). If the meter impedance changes the circuit impedance by more than, say, 5%, that is going to affect the observed value. (You pick the percent limit - it depends on the situation.) Even for the case with a high impedance meter, say a 10,000,000 Ohm Digital Multi-meter, impedance must be considered if the circuit impedance is high enough. (I have a WWVB receiver that requires a 1,000,000,000 Ohm voltmeter to correctly measure the AGC voltage - no ordinary digital multimeter will suffice.)This does not mean that you have to spend lots of money on a high performance, high impedance, meter. You simply have to consider what the impedance of the meter is going to do to the circuit, and calculate that impact, before you state the results.


What is mean by compensated and uncompensated power transmission line?

Power transmissions lines are inductive by nature. Power in AC systems is transmitted by varying the phase angle between source and receiving end following the below equation: Vsource * Vrecieve * sin (phi) / (Zsource + Zrecieve + Zline) V = the voltage phi = angle between source and receiving end voltage Z = impedance, Zsource = the impedance behind the source end Series compensating lines is accomplished by adding capacitors in series on a line, which reduces the Zline term in the above equation. This allows more power to be transmitted from one end to the other.


What is the characteristic impedance of free space and why do you think so?

Characteristic impedance (Z0) is defined as E/H ratio of {E,H} field. It depends on dielectric permettivity (epsilon), magnetic permettivity (mu) and geometry of region in which {E,H} propagates. For free space, it's easy to believe that geometry coefficient is 1 and in the end, you get -> Z0= square root (mu 0 / epsilon 0) = 120 pi, where subscript 0 means mu and epsilon referred to free space and pi=3.14... If you want to demonstrate that, you have to solve Maxwell's equation, imposing the condition of uniform plane wave travelling into free space, so you'll get an Helmholtz equation for Coulomb electric potential phi (you have to apply Lorentz's gauge condition and you'll get laplacian(phi) + k^2 phi = 0, where k=2*pi*frequency/c0 is called wave number). You solve this equation and put it into the equation linking magnetic potential vector (A) and phi. At this point, you can solve Maxwell equations and get E,H values and modulus ratio (Z0).

Related Questions

What is the impedance of a single phase inductive circuit having a voltage of 240volts and a current flow of 10amps?

Work it out for yourself. The equation is: Z = E/I, where Z is the impedance, E is the supply voltage, and I is the load current.


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 is this different from determining if a value is a solution to an equation?

How is this different from determining if a value is a solution to an equation?


What is the equation for determining pH?

pH = -log[H+]


Why is the exponent of a variable a determining factor in whether an equation is linear?

Because that is how a linear equation is defined!


What is the significance of the constant "t" in the equation?

The constant "t" in an equation represents time, and its significance lies in determining how the variables in the equation change over time.


How are equation coefficients useful in determining amounts of reactions and products?

Equation coefficients show the number of molecules involved in a chemical reaction.


After determining if two quantities are in inverse or direct you can find the equation's constant by solving for it?

variation


What is the Hazen-Williams formula for determining the capacity of a given pipe?

introdue the hazen william's equation


What is the equation for determining acceleration?

acceleration= change in velocity(m/s) divided by change in time(s)


How do you write out an equation used to find the inductive reactance ant the capacitive reactance?

Xc(capacitive reactance) = 1/(2piFC)XL(inductive reactance) = 2piFLWhere pi=3.14etc.,F=frequency and C and L are capacitance and inductance.Please pardon lack of proper symbology.


What is the analytical equation for determining the trajectory of a projectile?

The analytical equation for determining the trajectory of a projectile is the projectile motion equation, which is given by: y xtan - (gx2) / (2v2cos2) where: y is the vertical position of the projectile x is the horizontal position of the projectile is the launch angle g is the acceleration due to gravity (approximately 9.81 m/s2) v is the initial velocity of the projectile