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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 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.

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Will voltage drop across a capacitor?

basically a capacitor will charge to the input DC level however it will mathematically never happen since capacitors charge at a certain rate the voltage drop across a capacitor will follow the R C time constant or 63% of the applied voltage for a unit time.AnswerIn the case of an a.c. supply, yes, there will be a voltage drop across a capacitor. In the case of an 'ideal' capacitor, this will be the product of the load current and the capacitive reactance of the capacitor.


Why ac voltage is always applied across capacitor?

It's not.


When a capacitor is charged after 1 time constant the v across the capacitor is?

Depending on the circuit, 63% of the available voltage.


What is the total capacitance of this arrangement the charge of each capacitor and the voltage across the last capacitor and the energy stored in it?

(a) what is the total capacitance of this arrangement (B) the charge stored on each capacitor (C) the voltage across the 50 micro farad capacitor and the energy stored in it. 20v and 20+30+50 micro farad


Does voltage matter when charging a capacitor?

Yes, voltage matters when charging a capacitor. Capacitor charge rate is proportional to current and inversely proportional to capacitance. dv/dt = i/c So, voltage matters in terms of charge rate, if you are simply using a resistor to limit the current flow, because a larger voltage will attempt to charge faster, and sometimes there is a limit on the current through a capacitor. There is also a limit on voltage across a capacitor, so a larger voltage could potentially damage the capacitor.

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.


When a circuit consists of a capacitor and a resistor in series with a voltage source and the voltage across the resistor becomes zero then the capacitor is?

fully charged.


Why voltage across capacitor cant change instantaneously?

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.


IF capacitor that has been connected across a battery for comparatively long time becomes?

If the capacitor isn't punctured or failed, then it becomes charged to the voltage of the battery almost immediately after it's connected to it, and stays that way.


How do you charge a capacitor?

You charge a capacitor by placing DC voltage across its terminal leads. Make sure when using a polarized capacitor to place positive voltage across the positive lead (the longer lead) and negative voltage across the negative lead. Also make sure that the voltage you charge the capacitor to doesn't exceeds its voltage rating.


What happens to the charge if you double the voltage across a capacitor?

In order to double the voltage across a capacitor, you need to stuff twice as much charge into it.


Why does the voltage reading drop in measuring the potential difference across the capacitors?

Because the capacitor discharges. so voltage across the capacitor decreases.


What does a capacitor charge graph illustrate about the behavior of a capacitor in an electrical circuit?

A capacitor charge graph shows how the voltage across a capacitor changes over time when it is connected in an electrical circuit. It illustrates that initially, the voltage across the capacitor rises quickly as it charges up, but eventually levels off as the capacitor becomes fully charged. This graph helps to understand the time it takes for a capacitor to charge and how it behaves in a circuit.


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.


Will voltage drop across a capacitor?

basically a capacitor will charge to the input DC level however it will mathematically never happen since capacitors charge at a certain rate the voltage drop across a capacitor will follow the R C time constant or 63% of the applied voltage for a unit time.AnswerIn the case of an a.c. supply, yes, there will be a voltage drop across a capacitor. In the case of an 'ideal' capacitor, this will be the product of the load current and the capacitive reactance of the capacitor.


What happens to the current in a circuit as a capacitor charges?

What happens to the current in a circuit as a capacitor charges depends on the circuit. As a capacitor charges, the voltage drop across it increases. In a typical circuit with a constant voltage source and a resistor charging the capacitor, then the current in the circuit will decrease logarithmically over time as the capacitor charges, with the end result that the current is zero, and the voltage across the capacitor is the same as the voltage source.


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.