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Voltage leads current or, more specifically current lags voltage, in an inductive circuit. This is because an inductor resists a change in current.
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How capacitor and resitor in a circuit effect the phase of input voltage?
A capacitor and a resistor has no effect on the supply voltage; however, this particular load combination will cause the load current to lead the supply voltage by some angle termed the 'phase angle'.
A capacitive device in a single phase ac circuit causes the current waves to?
Lead the voltage waves
Does the current in a pure capacitive circuit lead or lag the applied voltage?
Answer #1Just remember our friend ELI the ICE man! E is voltage, I is current, L is inductance, and C is capacitance. ELI In an inductively reactive circuit (L), the voltage (E) comes first, then the current (I) lags behind. ICE In a capacitively reactive circuit (C), the current (I) leads, then the voltage (E) comes later. Note that while your assumption (in the stated question) is correct, an engineer or electrician would not say it that way. The voltage waveform is the constant, and the current waveform is said to lead or lag. This is because reactive or non-linear loads distort the current. If you look at a power-factor meter, and it says leading or lagging, it is referring to the current. It would be more accurate to re-phrase your question: In a capacitive reactive circuit does the current lead the voltage? Yes! Answer #2: Another method I learned from one of my EE professor is that in an inductor the current lags the voltage because the electrons get dizzy going through all of those loops (coils) in the inductor and "lag" behind the voltage.
How can current lag or lead voltage in an AC circuit isn't current a function of voltage etc?
Current can lag or lead voltage in an AC circuit when the load is what we call reactive. The idea that current is purely a function of voltage only applies when working with DC, or when working with purely resistive loads, such as light bulbs and toasters. Not so, when dealing with motors and power supplies. What happens is that an inductor resists a change in current. That means that, given a particular voltage and current at a particular instant of time, if you change the voltage, the current will not immediately follow - it will lag - because the inductor is a stored energy device. Similarly, a capacitor resists a change in voltage, which means that if you change the current, the voltage will not immediately follow - it will lag - also because the capacitor is a stored energy device. Flip over current and voltage in the analysis of a capacitor, and you find that the current will lead the voltage, as opposed to the inductor's current lagging the voltage. This causes the phenomenon of power factor, which is basically the cosine of the phase angle between voltage and current. Power factor is the ratio of apparent power to true power.
What is lagging and leading current?
Leading and lagging currents are not so much "currents" as they are "situations" or "conditions" in an electrical circuit. Reactive characteristics, if there are any, will not let voltage and current be in phase in a circuit. (Unless they are equal, and this will be true at only one frequency.) In some circuits, current leads voltage (or voltage lags current), and in other circuits, current lags voltage (voltage leads current), depending on the circuit and also on the frequency of the applied signal. In a capacitor, current leads voltage, and in an inductor, current lags voltage. This carries over to circuits that exhibit primarily capacitive or inductive characteristics. Additionally, reactance varies with frequency. As a given circuit with inductance and capacitance is evaluated, at some frequencies, it will appear capacitive, and current will lead voltage. At other frequencies, the circuit will appear inductive, and current will lag voltage. Only at a frequency where the reactances are equal will the current and voltage be in phase. The ideas here are best reviewed after achieving an understanding of the nature of inductance and capacitance, the associated reactances, and the way frequency affects these characteristics.
What is meant by lagging and leading circuit?
The terms, 'lagging' and 'leading', describe the relationship between a circuit's load current and supply voltage. They describe whether the load current waveform is leading or lagging the supply voltage -always the current, never the voltage. Inductive loads always cause the current to lag the supply voltage, whereas capacitive loads always cause the current to lead the supply voltage.
What is meant by lead and lag?
The terms, 'lagging' and 'leading', describe the relationship between a circuit's load current and supply voltage. They describe whether the load current waveform is leading or lagging the supply voltage -always the current, never the voltage. Inductive loads always cause the current to lag the supply voltage, whereas capacitive loads always cause the current to lead the supply voltage.
AC circuit that contains both resistance and inductance will have a.The current and voltage in phase b.current will lead the voltage c.current will lag the voltage d.voltage will lag the current?
a. the current and voltage in phase
Does the current lead or lag the voltage in a series A C circuit containing a large value of capacitance?
ICE current leads the voltage by 90 degrees.
How capacitor and resitor in a circuit effect the phase of input voltage?
A capacitor and a resistor has no effect on the supply voltage; however, this particular load combination will cause the load current to lead the supply voltage by some angle termed the 'phase angle'.
A capacitive device in a single phase ac circuit causes the current waves to?
Lead the voltage waves
What is the power factor of a DC system?
It would be unity, or 1.0. Since the voltage in a DC circuit does not vary with time, there can be no phase displacement of the current waveform, and therefore the current could not lead or lag the voltage waveform.
Does the current in a pure capacitive circuit lead or lag the applied voltage?
Answer #1Just remember our friend ELI the ICE man! E is voltage, I is current, L is inductance, and C is capacitance. ELI In an inductively reactive circuit (L), the voltage (E) comes first, then the current (I) lags behind. ICE In a capacitively reactive circuit (C), the current (I) leads, then the voltage (E) comes later. Note that while your assumption (in the stated question) is correct, an engineer or electrician would not say it that way. The voltage waveform is the constant, and the current waveform is said to lead or lag. This is because reactive or non-linear loads distort the current. If you look at a power-factor meter, and it says leading or lagging, it is referring to the current. It would be more accurate to re-phrase your question: In a capacitive reactive circuit does the current lead the voltage? Yes! Answer #2: Another method I learned from one of my EE professor is that in an inductor the current lags the voltage because the electrons get dizzy going through all of those loops (coils) in the inductor and "lag" behind the voltage.
How can current lag or lead voltage in an AC circuit isn't current a function of voltage etc?
Current can lag or lead voltage in an AC circuit when the load is what we call reactive. The idea that current is purely a function of voltage only applies when working with DC, or when working with purely resistive loads, such as light bulbs and toasters. Not so, when dealing with motors and power supplies. What happens is that an inductor resists a change in current. That means that, given a particular voltage and current at a particular instant of time, if you change the voltage, the current will not immediately follow - it will lag - because the inductor is a stored energy device. Similarly, a capacitor resists a change in voltage, which means that if you change the current, the voltage will not immediately follow - it will lag - also because the capacitor is a stored energy device. Flip over current and voltage in the analysis of a capacitor, and you find that the current will lead the voltage, as opposed to the inductor's current lagging the voltage. This causes the phenomenon of power factor, which is basically the cosine of the phase angle between voltage and current. Power factor is the ratio of apparent power to true power.
What is lagging and leading current?
Leading and lagging currents are not so much "currents" as they are "situations" or "conditions" in an electrical circuit. Reactive characteristics, if there are any, will not let voltage and current be in phase in a circuit. (Unless they are equal, and this will be true at only one frequency.) In some circuits, current leads voltage (or voltage lags current), and in other circuits, current lags voltage (voltage leads current), depending on the circuit and also on the frequency of the applied signal. In a capacitor, current leads voltage, and in an inductor, current lags voltage. This carries over to circuits that exhibit primarily capacitive or inductive characteristics. Additionally, reactance varies with frequency. As a given circuit with inductance and capacitance is evaluated, at some frequencies, it will appear capacitive, and current will lead voltage. At other frequencies, the circuit will appear inductive, and current will lag voltage. Only at a frequency where the reactances are equal will the current and voltage be in phase. The ideas here are best reviewed after achieving an understanding of the nature of inductance and capacitance, the associated reactances, and the way frequency affects these characteristics.
What is the relationship of current and voltage in a resistive circuit?
The current through the circuit is directly proportional to the voltage across the circuit. The proportionality constant is 1/R, where 'R' is the total effective resistance of the circuit. C = V / R V = C R R = V / C
Why capacitor behave as open circuit against alternating current?
Capacitors store electrical charge. Imagine we have a capacitor. At time 0 seconds we connect a DC voltage across the capacitor - immediately as the voltage is connected the capacitor is at 0 volts and the maximum current (relative to the circuit resistance) flows. At this extreme the capacitor can be treated as a short circuit, so for high frequency AC volts we should treat a capacitor as being a short circuit. As time passes the current in the circuit will go down and the voltage of the capacitor will go up - this is because as the capacitor gains more charge it gains more voltage, lowering the voltage across any resistance in the circuit consequently lowering the current in the circuit. When the capacitor is virtually full no current will flow at all and the voltage across the capacitor will equal the DC source voltage. At this extreme the capacitor can be treated as an open circuit, so for low frequency AC (allowing the capacitor to fill up before the current alternates) we can treat the capacitor as being an open circuit. Technically, it is not an open/closed circuit when it comes to AC because the capacitance will results in a signal lag or lead. However, if the frequency is low/high enough the lag/lead is often negligable.
