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Impede means to interfere with, block or slow something. For example, when you are impeding traffic, you are interfering with traffic, blocking or slowing it to less than ande…quate flow. (MORE)

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Answer The unit of measurement for impedance is the ohm.

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Impedance "Z" is measured in Ohms, same as resistance. The only difference is that this form of resistance is frequency dependent where induction or capacitances are involved.… Z = sqr(R2+X2) and in its complex from Z = R +jX where j = sqr(-1). The classical apparent power (V x I) will not apply as well as it apply in DC circuits. It would rather be in the form of P = Power Factor x V x I where Power Factor is PF= cos (angle) and angle = tan-1(X/R) since there is a phase shift between voltage and current due to the reactance (X) of the load, for inductive reactance the current lag, for capacitive reactances the current lead. I only use X as a general form of reactance, but normally reactance will either be: XL = 2 x Pi x f x L for inductive components or Xc = 1 / (2 x Pi x f x C) for capacitive components X, XL or Xc is also in ohms Impedance is Z and measured in Ohms and the same series - parallel laws apply as with resistances. When do you need to worry about impedance? when you work with alternating currents and not DC. When there are possible induction or capacitance involved which is the case most of the time. (MORE)

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In Grammar

"Impede" as a noun would be an "impedance." This is wrong. "Impedance" is a term relating to electrical conductance/resistance. The noun of "impede" is "impediment".

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In Technology

Impedance relays are used whenever over-current relays do not provide adequate protection. They function even if the short circuit current is relatively low. The speed of oper…ation is independent of current magnitude. Impedance relays monitor the impedance between the relay location and the fault. If the impedance falls within the relay setting, the relay will operate. The basic construction for impedance relays on which the principle of operation is easily explained is the balanced beam. (MORE)

If you are experiencing any of these symptoms, it may be time for you to get outside and catch some rays. … (MORE)

MaryLou Ross

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As it turns out, these stars actually regret the roles responsible for launching their careers into unforgettable stardom. After you read our explanations, perhaps you'll unde…rstand why. (MORE)

When it comes to basic facts, what you don't know can hurt you, or at the very least surprise you.… (MORE)

As the saying goes, you can't teach an old dog new tricks. Some tricks, however, are so simple that even an old dog or new puppy can learn them. Just practice any of the follo…wing a few times a day with your dog. (MORE)

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Z = SQR (R² + XL²) Where: Z = Impedance (ohm) R = Resistance (ohm) XL= Inductance reactance (ohm) Impedance is an AC resistance.

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In Technology

If you pretend that the signals in electric circuits are of the form A*exp(s*t), where A and s are constants, and t is time, then derivatives of the signal and integrations of… the signal are always just a scaled version of the signal. So, the ratio of voltage to current, when the signals are of this form, is just a (possibly complex) constant. This number is called impedance, and it depends on the value of the constant "s" in the signal. Impedance is a term used to signify a device that react to the flow of electrons in a negative way. It can be of complex passive devices or active devices. Impedance (symbol: Z), expressed in ohms, is the opposition to the flow of alternating current by a resistive-reactive load. It is the vector sum of resistance and reactance. (MORE)

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Here is one: I hope that the weight I have gained won't impede the progress I made in sports.

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In Technology

Impedance is the measurement of resistance that a circuit gives to current, which flows due to applied voltage. Impedance refers to the ratio of voltage to current and app…licable to a circuit with alternating current. (MORE)

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In Technology

The word "Impedance" is much over used, often to mean "resistance". The proper meaning of the word means the total impedance of a circuit, including the resistive, capacitive,… and inductive components. It is always frequency dependant, so that there are standard practices as to the frequency used to measure it. For example, a general purpose loudspeaker may be specified as having 8 ohms impedance. This takes account of the resistive, inductive, and capacitive components, usually at 1000 Hz. The antenna input to a TV set is usually 75 ohms (or maybe 50 ohms!), measured at some point in the middle of it's frequency range. It is always good to make sure that the antenna and feeder co-ax has the same characteristic impedance. (MORE)