So I am starting a discussion as to the aspects of a coil (L) vs a capacitor (C).
A capacitor will hold a charge for as long as the capacitor quality will allow and no resistance draining it. It resists changes in voltage by either charging or discharging until an equilibrium is reached. A coil will resist current change by increasing the magnetic charge or decreasing similar to a capacitor and voltage. Both The capacitor and the coil will resist change change within their domain. Both of these effects are used to reduce ripple in a power supply.
This is where it gets tricky. When you disconnect the capacitor from its voltage source it will maintain the same voltage across the leads. When you disconnect a coil from its current source it tries to maintain the same current with back EMF. If there is no resistance across the leads being present it was pulled it will create as much EMF voltage as it can to maintain this current which creates the inductive spike we are familiar with and must protect against occasionally. In the following schematic when the switch is opened The coil will discharge the current for 5 LR time constants similar to the five time constants a capacitor takes to charge / discharge a capacitor.
so when you push S1, the resistor will get a surge 100 ma, the coil L1 will be mostly will be completely discharged in five LR units. 1TC=0.0001 seconds (100µs).
So far so good?
A capacitor will hold a charge for as long as the capacitor quality will allow and no resistance draining it. It resists changes in voltage by either charging or discharging until an equilibrium is reached. A coil will resist current change by increasing the magnetic charge or decreasing similar to a capacitor and voltage. Both The capacitor and the coil will resist change change within their domain. Both of these effects are used to reduce ripple in a power supply.
This is where it gets tricky. When you disconnect the capacitor from its voltage source it will maintain the same voltage across the leads. When you disconnect a coil from its current source it tries to maintain the same current with back EMF. If there is no resistance across the leads being present it was pulled it will create as much EMF voltage as it can to maintain this current which creates the inductive spike we are familiar with and must protect against occasionally. In the following schematic when the switch is opened The coil will discharge the current for 5 LR time constants similar to the five time constants a capacitor takes to charge / discharge a capacitor.
so when you push S1, the resistor will get a surge 100 ma, the coil L1 will be mostly will be completely discharged in five LR units. 1TC=0.0001 seconds (100µs).
So far so good?
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