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Capacitors resist change in voltage. By definition, the equation is dv/dt = i/c, or rate of change of voltage in volts per second is current in amps divided by capacitance in farads. In order for the voltage to change instantaneously, then dv/dt must be infinity, which means i/c is also infinity. If capacitance is non-zero, then current must be infinity. Since there is no perfect voltage source, or no resistor or wire with perfect zero ohms, then it is impossible to have an infinite current, so it is impossible for the voltage across a capacitor to change instantaneously.

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Why do resistor voltage decrease while capacitor discharges?

The reason why resistor voltage decreases while a capacitor discharges is because the resistor acts like a source of electrical energy. As the capacitor discharges, it draws energy from the resistor, which causes the voltage across the resistor to decrease. This is because the capacitor is acting like a drain, and is taking energy out of the resistor, thus causing the voltage across the resistor to decrease. The resistor and capacitor work together in order to create a discharge circuit. This is done by connecting the capacitor to the resistor, and then to a voltage source. The voltage source supplies the energy to the resistor, and then the resistor transfers this energy to the capacitor. As the capacitor discharges, it takes energy from the resistor, which causes the voltage across the resistor to decrease. In order to understand this process better, it is important to understand the basics of Ohm's Law. Ohm's Law states that the voltage across a resistor is equal to the current through the resistor multiplied by the resistance. As the capacitor discharges, it takes energy from the resistor, which means that the current through the resistor decreases, and therefore the voltage across the resistor will also decrease.


Can you change a 35mF 425volts capacitor with a 20mf 410 volts capacitor?

Only if you are sure the voltage is less than 410 volts peak or it might fail. and- only if you are sure the reduced capacitance will not affect circuit operation. For most purposes, no, you should not do that.


How does voltage change across an appliance in a parallel circuit?

With the minor voltage loss in the wiring, the voltage drop across a single appliance is the total voltage in the circuit, and doesn't change when more devices are added in parallel.


What is the difference between capacitor and capacitance?

A capacitor is a device that stores an electrical charge, or if you prefer- resists any change in voltage applied to it. Capacitance is a measure of the size or ability of a capacitor to do that. This is the Farad


Why alternating current induce voltage across an inductor?

due to change in flux

Related Questions

Can the voltage across a capacitor change instantaneously?

No, the voltage across a capacitor cannot change instantaneously. It takes time for the voltage across a capacitor to change due to the storage and release of electrical energy in the capacitor.


Voltage across capacitor cannot becomes zero instantaneously prove?

Capacitors resist change in voltage. By definition, the equation is dv/dt = i/c, or rate of change of voltage in volts per second is current in amps divided by capacitance in farads. In order for the voltage to go to zero instantaneously, then dv/dt must be infinity, which means i/c is also infinity. If capacitance is non-zero, then current must be infinity. Since there is no perfect voltage source, or no resistor or wire with perfect zero ohms, then it is impossible to have an infinite current, so it is impossible for the voltage across a capacitor to go to zero instantaneously.


How does the voltage across a capacitor change over time when a current is flowing through it?

When a current flows through a capacitor, the voltage across it increases or decreases depending on the rate of change of the current. If the current is constant, the voltage remains steady. If the current changes rapidly, the voltage across the capacitor changes quickly as well.


What is the relationship between capacitor current and voltage in an electrical circuit?

The relationship between capacitor current and voltage in an electrical circuit is that the current through a capacitor is directly proportional to the rate of change of voltage across it. This means that when the voltage across a capacitor changes, a current flows to either charge or discharge the capacitor. The relationship is described by the equation I C dV/dt, where I is the current, C is the capacitance of the capacitor, and dV/dt is the rate of change of voltage with respect to time.


How does the voltage across a parallel plate capacitor change when connected to a battery?

When a parallel plate capacitor is connected to a battery, the voltage across the capacitor increases as it charges. The battery provides a potential difference that causes charges to accumulate on the plates, leading to an increase in voltage until the capacitor is fully charged.


What is the phase relationship of voltage across a capacitor and current though the capacitor?

In a capacitor, the current LEADS the voltage by 90 degrees, or to put it the other way, the voltage LAGS the current by 90 degrees. This is because the current in a capacitor depends on the RATE OF CHANGE in voltage across it, and the greatest rate of change is when the voltage is passing through zero (the sine-wave is at its steepest). So current will peak when the voltage is zero, and will be zero when the rate of change of voltage is zero - at the peak of the voltage waveform, when the waveform has stopped rising, and is about to start falling towards zero.


Why do resistor voltage decrease while capacitor discharges?

The reason why resistor voltage decreases while a capacitor discharges is because the resistor acts like a source of electrical energy. As the capacitor discharges, it draws energy from the resistor, which causes the voltage across the resistor to decrease. This is because the capacitor is acting like a drain, and is taking energy out of the resistor, thus causing the voltage across the resistor to decrease. The resistor and capacitor work together in order to create a discharge circuit. This is done by connecting the capacitor to the resistor, and then to a voltage source. The voltage source supplies the energy to the resistor, and then the resistor transfers this energy to the capacitor. As the capacitor discharges, it takes energy from the resistor, which causes the voltage across the resistor to decrease. In order to understand this process better, it is important to understand the basics of Ohm's Law. Ohm's Law states that the voltage across a resistor is equal to the current through the resistor multiplied by the resistance. As the capacitor discharges, it takes energy from the resistor, which means that the current through the resistor decreases, and therefore the voltage across the resistor will also decrease.


What does the continuity of capacitor voltage mean?

It might mean that the voltage across a capacitor cannot change instantanteously because that would demand an infinite current. The current in a capacitor is C.dV/dt so with a finite current dV/dt must be finite and therefore the voltage cannot have a discontinuity.


How does capacitance change with voltage?

Capacitance is a measure of how much charge a capacitor can store for a given voltage. As the voltage across a capacitor increases, the capacitance typically remains constant. However, in some cases, the capacitance may change slightly due to factors like dielectric breakdown or non-linear effects.


Why capacitor oppose change in voltage and allows current to flow?

Because that is what a capacitor does, resist a change in voltage. It holds a certain amount of energy per charge (voltage), and to change that voltage requires current proportionally to the capacitance.


What is the value of capacitor voltage and current after 5 time constant?

After 5 time constants, capacitor voltage/current will be about 99.3% of the input step change.


What determine the flow of charge through a conductor?

Charges may appear to flow through a capacitor, although in reality they don't.The degree to which charge appears to flow through a capacitor depends on therate at which the voltage across it changes.-- DC voltage doesn't change, so it doesn't appear to pass through a capacitor at all.-- AC voltage is always changing, and the higher its frequency, the more currentit appears to push through a capacitor.