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By adding capacitors or inductors in series (typically lower power) or parallel (higher power power factor correction); the choice of capacitor or inductor depends on whether the reactive resistance is "leading" or "lagging". A capacitor is modelled 1/jCw, where w = frequency in rads; an inductor is modeled jLw. If you know the reactive resistance, and the system frequency, you can calculate how much capacitance/inductance is needed.
What else can I help you with?
When load on a normally excited synchronous motor is increased its power factor tends to what?
approach unit
What is the difference between lagging and leading power factor?
Power factor is the ratio of watts (true power) to VA (volt-amperes, also called apparent power). Where the load is resistive only, the power factor is one, or unity, because the voltage waveform and the current waveform are in phase. Thus, for resistive loads only, true power and VA are the same. Where the load is reactive, the load stores energy, releasing it during a different part of the cycle. This shifts the current waveform so that it is offset, or out of phase with the voltage waveform. Reactive loads can be inductive (electric motors), capacitive, or non-linear (rectifier power supplies). When the load is inductive, the inductance tends to oppose the flow of current, storing energy then releasing it later in the cycle. The current waveform lags behind the voltage waveform. When the load is capacitive, the opposite occurs, and the current waveform leads the voltage waveform. So, lagging vs. leading is another way of saying the net reactance is either inductive or capacitive. This is slightly simplistic, and what we are talking about above is really DPF, or Displacement Power Factor. Non-linear loads don't really shift the current waveform, they distort it. The current waveform starts to look like a square wave, and square waves contain harmonics. So non-linear loads add harmonic distortion, and this tends to mimic a capacitively reactive load, adding some leading power factor. So when we say power factor, we really must include DPF plus harmonic distortion in total. One memory aid that may help to remember all this is: ELI the ICE man The L in ELI means inductance. The E (voltage) comes first, then the I (current) lags behind. Inductive reactance produces a lagging power factor. The C in ICE means capacitance. The I (current) comes first (leads) then the E (voltage) comes later. Capacitive reactance produces a leading power factor. Remember, it's always the current waveform that is affected by the reactive load, so you have to think about whether the current is leading or lagging. Most reactive loads are inductive, so at most sites the PF is lagging. One cool tidbit is that capacitive reactance cancels out inductive reactance. So if we have a building full of motors, we can add a bunch of capacitors to improve our power factor, meaning we get as close to unity as we can. Thus we have power factor correction capacitors that are made just for this purpose.
Explain how you can determine the type of correlation for a set of data pairs by examining the data in a table without drawing a scatter plot?
"If y tends to increase as x increases, then the data have a positive correlation. If y tends to decrease as x increases, then the data have a negative correlation. If the points show no correlation, then the data have approximately no correlation."
Why do you connect a capacitor panel to the load?
Capacitors are sometimes connected in parallel to inductive loads to improve the power factor, raising the voltage of the source AC. Power factor is the ratio of apparent power over true power. It is 1, if the load is purely resistive, such as in a toaster, but it is less than 1 if the load is reactive, such as in a motor. This is because current is not in phase with voltage in that case. Inductive loads cause the current to lag voltage, and capacitive loads cause the current to lead voltage. Placing capacitors across an inductive load tends to compensate for the lagging power factor. Specifically, power factor is the cosine of the phase angle between voltage and current. In an ideal situation, with perfect sources, conductors, and reactive loads, the phase angle would be plus (capacitive) or minus (inductive) 90 degrees, and the power factor would be zero. This means that a conventional watt meter would register zero but, in reality, energy is still being supplied, and that has to be accounted for. In practical terms, since conductors have impedance, a poor power factor degrades voltage so, adding capacitors raises voltage.
Suppose a wire of resistance R could be stretched uniformly until it was twice its original length. What would happen to its resistance?
Current tends to travel on the surface of the wire. As you decrease the cross-sectional area of a wire the resistance increases. That is why larger wires are rated for higher currents.
The of a circuit tends to slow down the movement of electrons?
The "impedance" of a circuit slows down the movement of electrons. This can be resistive, reactive or a combination of both.
How does reactive power change the Power Factor?
Power Factor is the relationship between the phase of the current and voltage which are each sine waves. When there is an inductance in a circuit the AC current waveform tends to lag the voltage. This causes a phase difference which reduces the Power Factor from a maximum of one to something less.
Does alcohol consumption tends to decrease or increase self awareness?
Decrease
True or False The chemical reactivity of metals tends to increase from left to right across the periodic table?
False. The most chemically reactive metals are in the two leftmost columns.
The total amount of usable energy tends to increase in a closed system?
No. It tends to decrease.
Is francium more or less reactive than cesium?
Francium is more reactive than cesium. It is the most reactive metal due to its position in the periodic table - the farther down and to the left an element is, the more reactive it tends to be.
As something increases what decreases?
As the price of a product increases, the demand for that product tends to decrease due to higher costs for consumers. Additionally, as the temperature decreases, the speed of chemical reactions tends to decrease as well.
Is selenium or sulfur more reactive?
sulfur is more reactive than selenium
How reactive is osmium?
Osmium has varying states of reactivity. Its pure state tends be quite reactive and is rarely used unless alloyed. Osmium tetroxide is extremely reactive, whereas osmium dioxide has very little reactivity.
What element is a more reactive metal Te or Ag?
Ag (silver) is a more reactive metal compared to Te (tellurium). Silver tends to readily react with various elements and compounds, while tellurium is relatively less reactive.
Is carbon more reactive than chlorine?
Chlorine is more reactive than carbon. Chlorine belongs to group 17 of the periodic table, meaning it has 7 valence electrons and tends to form one additional covalent bond. Carbon, on the other hand, is in group 14 and tends to form 4 covalent bonds, making it less reactive than chlorine.
Is copper more reactive than tin?
No, copper is less reactive than tin. Tin reacts readily with acids, but copper is less reactive and tends to form a protective layer of oxide on its surface, making it more resistant to corrosion.
