The effects of connecting 10V battery to a 5V capacitor

[potatoe]

If battery have 10 volts and capacitor can charge about 5 volts is maximum as show in picture below .
When switched is on,how many Imax and how about capacitor.
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[Rumieus]

Re: about capacitor

Im not answering your question.

From my understanding.

Since the resistor is place after the capacitor, so the capacitor will charge instantly to its max in 0s and the current is the same since it's a series circuit. Calculate the I using ohm law.

Is that right? If not, please explain. tq

 

[jony130]

Re: about capacitor

Since the resistor is place after the capacitor, so the capacitor will charge instantly to its max in 0s and the current is the same since it's a series circuit. Calculate the I using ohm law.
Is that right? If not, please explain. tq

No
In this circuit capacitor is in series with the resistor.
Assuming that C1 is not initially charged, when the switch is first closed, a current will begin to flow.
The rate of the current flow (which determines how rapidly the capacitor will charge) will be limited by the series resistance
in the circuit, and the difference in potential between the capacitor and the source.
So when the switch is close the current is start to flow.
Because capacitor is empty the whole battery voltage apply to the R1.
So the max current Imax=10V/10KΩ=1mA.
As the capacitor begins to charge (build up voltage), the rate of current flow from the source to the capacitor begins to decrease.
So the voltage on the capacitor rise, and after some time T=RC=10uF*10KΩ=0.1s capacitor will be charge to 6.3V. And the voltage on resistor will be Vr=10V-6.3V=3.7V. So the charge current is equal I=3.7V/10KΩ=0.37mA=370uA
And after T=5*RC=0.5s capacitor eventually charges to the full source potential of 10 volts. When this happens, all circuit current will stop flow, because there can be no current flow through the dielectric. If switch is opened at this time, the capacitor will hold this static charge (Voltage) until given a discharge path of lesser potential. In this circuit their is non discharge path, so the capacitor will hold the voltage.

 

[potatoe]

Re: about capacitor

In this circuit capacitor can endure voltage 5 volts but source can supply 10 volts.In this case ,What's happen on capacitor.

 

[jony130]

Re: about capacitor

If it's a electrolytic capacitor he can even explode

Three sure ways to kill an electrolytic capacitor:

1. Overvoltage: If the specified voltage is exceeded, current will leak through the isolation, not in a slow way that might regenerate weak areas, but violently, creating hotspots where additional break-down occurs. The danger of explosion is imminent.
2. Reversed polarity: As described, the inverse of regeneration = self destruction, will occur. If the applied voltage is near the normal (right polarity) working voltage, break-down is quick and violent. The effect of a low inverse voltage might be reversible.
3. Heat. Heat shortens the life of an electrolytic capacitor. A good rule of thumb is that every 10deg C over 85 will cut the life expectancy in half.

The rules for a long peaceful life are, of course, the opposite. When replacing electrolytic capacitors in old equipment, never, never go below the voltage rating of the original parts. Modern componets are usually more compact, so if you cannot get the exact rating, choose a higher one, there will usually be room for it. If wrong polarization or overvoltage has caused an electrolytic capacitor to become hot, discard it. Look out for heat sources; in old power supplies, there is often a large hot drop resistor placed near the filter capacitor, make sure it doesnt transfer too much heat to the capacitor.

 

[sushain]

Re: about capacitor

It is dangerous to connect a 5V capacitor to 10 volt supply. For obvious reasons there would be a dielectric breakdown and the capacitor will burst.

 

[xulfee]

about capacitor

dielectric breakdown will occure