Which of the following capacitors has the highest cost per F?
Plastic
Air
Mica
Electrolytic
Correct Answer :
D. Electrolytic
Related Questions
A rheostat is a form of
Variable resistor
Variable capacitor
Potentiometer
Thermocouple
When two coils of identical reactance are in parallel without mutual inductancea the reactance of the combination is ___ the reactance of each coil.
One half
Twice
Four times
One fourth
Which of the following describes the action of a capacitor?
Stores electrical energy
Opposes changes in current flow
Creates a dc resistance
Converts ac to dc
In an ac circuita the power dissipated as heat depends on
Impedance
Capacitive reactance
Resistance
Inductive reactance
A real current source has
Infinite internal resistance
Zero internal resistance
Large internal resistance
Small internal resistance
The reciprocal of a complex number is
A complex number
A real number
An imaginary number
A whole number
A capacitive load always has a ______ power facto
Leading
Lagging
Zero
Unity
What is considered as the most important value of a sine wave?
Effective value
Peak value
Average value
Instantaneous value
In liquids and gasesa ionization current results from a flow of
Positive or negative ions
Free electrons
Ions that are lighter in weight than electrons
Protons
If the capacitance of mica capacitor is 5 times the capacitcitora then the relative permittivity of mica is
For parallel capacitorsa total charge is
The sum of individual charges
Equal to the charge of either capacitors
Equal to the product of the charges
The quotient of the charges
What increases the resistance of wire at high frequencies?
Temperature
Voltage
Skin effect
Insulation
For greater accuracya the value of phase angle should be determined from
Cos
Tan
Sin
Sec
The resistance of an insulator ___ when its temperature is increased.
Decreases
Remains the same
Increases
Varies
The ratio of maximum value to the effective value of an alternating quantity is called
Form factor
Peak factor
Dynamic factor
Leakage factor
Series resonance occurs when
XL= XC
XL= R
Z = R
Both A and C
Voltage resonance means
Series resonance
Parallel resonance
Current magnification
Gain magnification
Form its definitiona the unit of electric fielda is the N/C and equivalent unit of is the
V(m)2
V(m)
V/m2
V/m
A series RLCcircuit consists of a 10 resistor in series with L = 10 Ha and C= 100 F. Determine a new value of Ia for which the resonant frequency is one ±half the original value.
40 H
40 mH
40 pH
40 nH
What is the total capacitance of 10 capacitorsa each of 20 F in series?
200 F
2 F
100 F
0.5 F
A series RLCcircuit has a ______ power factor at its half-power points
Unity
Leading
Lagging
Either B or C
What is the specific resistance of a pure silicon?
55 -mm
55 -m
55 -cm
55 k -m
What is the complex impedance of a circuit with an absolute resistance of 300 ?
0 + j 300
300 + j 90
0 ± j 300
300 +j 0
An open resistor when checked with an ohmmeter reads
Zero
Infinite
High but within the tolerance
Low but not zero
The Q-factor of a series resonant circuit is also known as
Current magnification factor
Voltage magnification factor
Load factor
Leakage factor
For a series ACcircuita ___ is not used as a reference phasor.
Voltage
Impedance
Current
Conductance
The presence of an electric current is made known by
Electric shock
Effects produced
Magnetic shock
Flashing
What is the reading of an ohmmeter for a shorted capacitor?
Zero
Infinity
k
M
A capacitance of 0.05 F equals
0.05 x 106F
0.05 x 10-6F
0.05 x 10-12F
0.05 x 1012F
Which of the following is also known as antiresonant circuit?
Parallel resonant circuit
Series resonant circuit
Tuned circuit
Tank circuit