Carl Pugh said:Homework ?
uart said:If Vb is the battery (voltage source) voltage and Vc is the initial capacitor voltage then :
The energy gained by the voltage source is Vb*Q = Vb C ( Vc - Vb )
The reduction in stored energy in the capacitor is 1/2 * C ( Vc^2 - Vb^2 )
The energy lost is the difference of the above, which equals 1/2 * C (Vc - Vb)^2.
Note that this energy loss is independent of the value of the resistor used to connect the two.
seahs said:Can the voltage source gain energy? what if the voltage source is like a non-rechargeable battery?
The purpose of discharging a high voltage capacitor using a low voltage source is to safely remove any residual charge from the capacitor. This is important for preventing accidental shocks or damage to electronic components.
The low voltage source, typically a resistor, is connected to the capacitor and allows the excess charge to slowly dissipate. This prevents a sudden discharge of high voltage, which can be dangerous.
No, it is important to use a low voltage source with the appropriate resistance to safely discharge a high voltage capacitor. Using a source with too low resistance can cause a sudden and potentially harmful discharge.
The time it takes to discharge a high voltage capacitor using a low voltage source depends on the capacitance of the capacitor and the resistance of the low voltage source. It can range from a few seconds to several minutes.
Yes, it is necessary to discharge a high voltage capacitor before handling it to avoid any potential risks. Even if the capacitor has not been in use for a while, it is always best to discharge it before handling it to ensure safety.