in case of inductor or capacitor power factor is always zero.as power factor is cosine of phase angle between voltage and current. in case of inductor and capacitor phase angle between voltage and current is 90 so it become zero so if given power factor is zero then it can be inductor or capacitor.
the bridge is preferably balanced by capacitor parallel attached resistance value. so, q factor of the inductor is given by w L / C at balance condition. q-value is low prefer
A capacitor is used to improve the power factor of the lamp.More detailsTo prevent the lamp from taking too much current a fluorescent lamp has to have a choke, which has magnetic inductance. The inductance has a negative impact on the power factor of the (the ratio between apparent power and real power taken by the lamp) - i.e. the power factor is reduced - so a capacitor is used to compensate for the inductance by improving the power factor so that it is closer to the ideal value of 1.Basically the inductor with the capacitor smooths out the voltage or current.
Inductor impedance is given by jwL, where w=2*pi*frequency. Therefore as the frequency increases the impedance of the inductor increases, causing a larger current flow and a larger power dissipation across the inductor
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.
schering's bridge is used to measure capacitance and dissipation factor of a capacitor. AC voltage is given to the terminals of bridge and bridge is balanced by varying resistance and capacitance in the opposite arm.
the bridge is preferably balanced by capacitor parallel attached resistance value. so, q factor of the inductor is given by w L / C at balance condition. q-value is low prefer
You surely do mean inductor, not capacitor. The length is not enough to determine the number of windings for an inductor. Inductance is bound with following parameters by equation: L = (pi/4) * mi * (N * d)^2 / l, where: L - inductance mi - permeability of inductor core N - number of windings d - diameter of inductor l - length of inductor Using those data, you can transform the equation to: N = sqrt(2*L*l/(mi*pi))/d
A capacitor is used to improve the power factor of the lamp.More detailsTo prevent the lamp from taking too much current a fluorescent lamp has to have a choke, which has magnetic inductance. The inductance has a negative impact on the power factor of the (the ratio between apparent power and real power taken by the lamp) - i.e. the power factor is reduced - so a capacitor is used to compensate for the inductance by improving the power factor so that it is closer to the ideal value of 1.Basically the inductor with the capacitor smooths out the voltage or current.
When an LC tank is excited at the resonant frequency, the energy across each will be equal (but not necessary equal at a given moment in time). If excited at a frequency other than the resonant frequency, the impedance of the inductor (wjL) and capacitor (1/wjC) will not be equal, therefore energy across each will be different.
LC filter It is a combination of inductor and capacitor filter. Here an inductor is connected in series and a capacitor is connected in parallel to the load as shown in fig 5.6. As discussed earlier, a series inductor filter will reduce the ripple, when increasing the load current. But in case of a capacitor filter it is reverse that when increasing current the ripple also increases. So a combination of these two filters would make ripple independent of load current. The ripple factor of a chock input filter is given by Since the d.c. resistance of the inductor is very low it allows d.c. current to flow easily through it. The capacitor appears open for d.c. and so all d.c. component passes through it. The capacitor appears open for d.c. and so all d.c components passes through the load resistor RL. Bleeder resistor For optimum functioning, the inductor requires a minimum current to flow through, at all time. When the current falls below this rat, the output will increase sharply and hence the regulation become poor. To keep up the circuit current above this minimum value, a resistor is permanently connected across the filtering capacitor and is called bleeder resistor. This resistor always draws a minimum current even if the external load is removed. It also provides a path for the capacitor to discharge when power supply is turned off.
LC filter It is a combination of inductor and capacitor filter. Here an inductor is connected in series and a capacitor is connected in parallel to the load as shown in fig 5.6. As discussed earlier, a series inductor filter will reduce the ripple, when increasing the load current. But in case of a capacitor filter it is reverse that when increasing current the ripple also increases. So a combination of these two filters would make ripple independent of load current. The ripple factor of a chock input filter is given by Since the d.c. resistance of the inductor is very low it allows d.c. current to flow easily through it. The capacitor appears open for d.c. and so all d.c. component passes through it. The capacitor appears open for d.c. and so all d.c components passes through the load resistor RL. Bleeder resistor For optimum functioning, the inductor requires a minimum current to flow through, at all time. When the current falls below this rat, the output will increase sharply and hence the regulation become poor. To keep up the circuit current above this minimum value, a resistor is permanently connected across the filtering capacitor and is called bleeder resistor. This resistor always draws a minimum current even if the external load is removed. It also provides a path for the capacitor to discharge when power supply is turned off.
LC filter It is a combination of inductor and capacitor filter. Here an inductor is connected in series and a capacitor is connected in parallel to the load as shown in fig 5.6. As discussed earlier, a series inductor filter will reduce the ripple, when increasing the load current. But in case of a capacitor filter it is reverse that when increasing current the ripple also increases. So a combination of these two filters would make ripple independent of load current. The ripple factor of a chock input filter is given by Since the d.c. resistance of the inductor is very low it allows d.c. current to flow easily through it. The capacitor appears open for d.c. and so all d.c. component passes through it. The capacitor appears open for d.c. and so all d.c components passes through the load resistor RL. Bleeder resistor For optimum functioning, the inductor requires a minimum current to flow through, at all time. When the current falls below this rat, the output will increase sharply and hence the regulation become poor. To keep up the circuit current above this minimum value, a resistor is permanently connected across the filtering capacitor and is called bleeder resistor. This resistor always draws a minimum current even if the external load is removed. It also provides a path for the capacitor to discharge when power supply is turned off.
Inductor impedance is given by jwL, where w=2*pi*frequency. Therefore as the frequency increases the impedance of the inductor increases, causing a larger current flow and a larger power dissipation across the inductor
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.
i know that static capacitors are used to improve the power factor. power factor should be high. Static capacitor supplies lagging reactive power. That means; the current I has 2 components they are magnetising Im (watless or waste current) and useful current Iw. Iw is in phase with voltage and Im is 90 degree away. Phase angle between them is phi 1. power factor is given by cosine of phi 1. phi angle should be less so that cosine of phi is high. To make phi angle less we use capacitor; this is nothing but power factor correction and capacitor used for this is called power factor correction capacitor. now when a capacitor is connected, it induces a current Ic 180 out of phase from Im and less in magnitude from Im. therefore, now the magnetising current is Im1=Im-Ic. due to this the phase angle reduces to phi 2. now the new power factor is cosine of phi 2. it is improved power factor.
schering's bridge is used to measure capacitance and dissipation factor of a capacitor. AC voltage is given to the terminals of bridge and bridge is balanced by varying resistance and capacitance in the opposite arm.
google is your friend. http://en.wikipedia.org/wiki/Capacitor google is your friend. http://en.wikipedia.org/wiki/Capacitor