Upgrade to remove ads
Ch. 12 DC Circuit Capacitance
Terms in this set (25)
What are the three different standards systems used for identifying capacitors?
The three different standards systems used for identifying capacitors include the Joint Army-Navy (JAN), Electronics Industries Association (EIA), and International Electrotechnical Commission (IEC).
What units are most capacitors rated in?
Most capacitors are rated in microfarads (µF) or picofarads (pF).
Why is the dielectric breakdown that occurs through air or oil insulation temporary?
Air and oil insulation recover their dielectric strength once voltage is removed from the circuit.
How are capacitors that overheat repaired?
Capacitors that overheat cannot be repaired. They are discarded and replaced.
What occurs when capacitor plates are too close together?
If capacitor plates are too close together, electrons may arc across the gap, causing degradation of the dielectric and damage to the capacitor
Where are oil-filled capacitors primarily used?
Oil-filled capacitors are primarily used as filters in the output of high-voltage DC power supplies.
What is the capacitance for 5C of change for 6V?
C = Q /V
C = 5 C/ 6 V
C = 0.83 F
What is the time constant of a 5F capacitor charged through a
τ = RC
τ = 3 Ω × 5 F
τ = 15 sec
What causes dielectric hysteresis loss?
Dielectric hysteresis loss is the result of dielectric impurities in the dielectric.
Why is leakage current considered to be undesirable in a capacitor?
Leakage current is typically considered undesirable because it flows through the dielectric
List three factors that affect the capacitance of a circuit.
area of the plates,thickness of the dielectric material, dielectric constant of the dielectric material
What is the capacitance for 3C of change for 12V?
C = Q/ V
C = 3 C/ 12 V
C = 0.25 F
What is a resistive-capacitive time constant?
A resistive-capacitive time constant is the amount of time required for a capacitor to charge to 63.2% of the maximum voltage across a resistive-capacitive circuit.
What is supercapacitor?
A supercapacitor is a capacitor that offers high capacitance in a small volume.
What is capacitance?
Capacitance is the ability of a component or circuit to store energy in the form of an electrical charge.
What is the main advantage of a supercapacitor over a battery?
Because there is no current limit when charging a supercapacitor, the recharging time is greatly reduced.
List 5 types of leads used with aluminum electrolytic capacitors.
axial leads; radial leads; flying leads; tab leads; screw leads; gull wing leads; J-leads
What is a dielectric constant?
A dielectric constant (k) is the ratio of the capacitance of a capacitor with a given dielectric to the capacitance of a capacitor with air (vacuum) as the dielectric.
What is dielectric breakdown in a capacitor the result of?
Dielectric breakdown is the result of the orbital electrons in the dielectric becoming free current-carrying electrons.
What is the time constant of a 0.5 F capacitor charged through a
τ = RC
τ = 5 Ω × 0.5 F
τ = 2.5 sec
What is the capacitance for 2C of charge for 1V?
C = Q /V
C = 2 C/ 1 V
C = 2 F
What is used as the dielectric for variable capacitors?
Air or mica is used as the dielectric for variable capacitors.
Why must polarity be observed with a polarized capacitor?
Polarity must be observed with a polarized capacitor because mismatched polarities on the connection leads of a polarized capacitor will damage the capacitor and cause an explosion, potentially harming anyone within the vicinity of the capacitor.
How are capacitance and voltage ratings identified on multiple-unit capacitors?
Capacitance and voltage ratings are identified on multiple-unit capacitors by geometric shapes printed on the body of the capacitors.
When does current flow cease in a capacitive circuit with DC voltage applied?
Current fl ow ceases when the capacitive voltage equals the value of the source voltage.
THIS SET IS OFTEN IN FOLDERS WITH...
Ch. 19 Resonance
CH. 20 Three-Phase AC
Ch. 1 Basic Concepts of electricity
Ch. 21 Transformers
OTHER SETS BY THIS CREATOR
Ch. 18 Inductive
Ch. 16 Inductive AC Circuits
Ch. 15 Resistive AC Circuits
OTHER QUIZLET SETS
QUIZ: Chapter 8: Race and Ethnicity
Linux 2 Week 1
Habitability of Mars
Ch 24 ASSESSING MUSCULOSKELETAL SYSTEM