Unit 17 Flashcards
A capacitor plate that has an excess amount of electrons holds what kind of charge?
Negative
The force that attracts electrons is called what?
Electric field
How do you discharge a capacitor?
Conduct a path connected across both terminals of the conductor.
Because a capacitor introduces reactance to the circuit, it causes the voltage waveform to ____ the current waveform.
Lag
What do you call devices that intentionally introduce capacitance into circuits?
Capacitors
A capacitor permits current to flow because of its ability to _____ energy and then discharge the energy as the ac current flows in the opposite direction
Store
A capacitor responds to changes in current by increasing or decreasing its own amount of ______
Charge
In capacitors, the less the surface area of the plates, the _______ the capacitance
Less
What happens if a capacitor is overcharged?
The electrons from the negative plate can be pulled through the insulation (dielectric) to the positive plate and the capacitor is said to have broken down (shorted).
What are the two main uses of capacitors?
Start single-phase ac motors and smooth out pulsating dc waveforms
(T/F) When power is removed from the circuit, the capacitors no longer store energy.
False
_______ is the property of an electrical circuit that enables it to store electrical energy by means of an electric field and to release that energy at a later time
Capacitance
A capacitor resists changes in _____
Current
The opposition offered to the flow of ac current by a capacitor is called what?
Capacitive reactance
Dielectric strength indicates the maximum _____ that can be applied across the dielectric safely.
voltage
