Effects of capacitance
It opposes any change in the amount of voltage
Voltage is lagged behind the current by a quarter cycle
Electric energy is stored in the capacitor in the form of electrostatic field
All of the above
Correct Answer :
D. All of the above
Related Questions
Why are inductance and capacitance not relevant in a dc circuit?
Because it is a simple circuit
Because dc circuits require only resistance as load
Because they do not exist in a dc circuit
Because frequency of dc is zero
If three 100-pF capacitors are connected in seriesa then the total capacitance is
300 pF
100 pF
50 pF
33.3 pF
Which of the following is the most popular waveform?
Sinusoidal
Square wave
Triangular
Sawtooth
The capacitor opposes any change in voltage across it by
Passing a voltage proportional to the rate of change of current
Acting as a short circuit at time equal to zero
Passing a current proportional to the rate of change of voltage
Acting as a short circuit at time equal to infinity
An inductive load always has a ___ power factor
Leading
Lagging
Zero
Unity
What determines the direction of induced emf in a conductor or coil?
Cork screw rule
Fleming�s left hand rule
Ampere�s circuital law
Fleming�s right hand rule
For greater accuracya the value of phase angle should be determined from
Cos
Tan
Sin
Sec
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
A trigger circuit consisting of a capacitor of 0.01 F is connected in series with a resistor. If the circuit requires 100 Vdcto operatea determine the value of the resistor when time constant is 0.009s.
900 k
900 M
900 G
What is expected when two 20 k a 1 watt resistor in parallel are use instead of one 10 k a 1 watt?
Provides higher current
Provides less power
Provides more power
Provides wider tolerance
The presence of an electric current is made known by
Electric shock
Effects produced
Magnetic shock
Flashing
Kirchhoff�s laws (KCL and KVL) are applicable to
DCcircuits
ACcircuits
DC as well as AC circuits
Passive networks alone
In a circuita an active element is one which
Supplies energy
Receives energy
Both supplies and receives energy
Amplifies signal
What can be used to estimate resonant frequency and to find reactance at any frequency for any value of capacitor or inductor?
Smith chart
Reactance chart
Impedance chart
Resonance chart
An intermittent and non-symmetrical alternating current like that obtained from the secondary winding of an induction coil
Faradic current
Transient ac current
Inductive current
Capacitive current
In a series circuit with unequal resistances the
Highest R has the highest V
Lowest R has the highest V
Lowest R has the highest I
Highest R has the highest I
A gang capacitor is a variable capacitor in which capacitance is varied by changing the
Dielectric
Number of plates
Plate area
Distance between plates
Thevenin�s theorem is what form of an equivalent circuit?
Current
Voltage
Both current and voltage
Neither current nor voltage
The voltage lags the current by cycle in a
Purely resistive circuit
Purely inductive circuit
Purely capacitive circuit
Circuit containing resistancea capacitance and inductance
A wire of one kilometre length has a resistance of 20 . If the length is halveda then the new resistance is ___ the original resistance.
Half
Twice
One-fourth
Three times
In an ac wavea 30 degrees of phase is ___ of a cycle.
½
Points to be considered in choosing a capacitor
Working voltage
Type of dielectric
Capacitance
All of the above
High resistance values are a consequence of the ___ of the film.
Thickness
Length
Thinness
Area
Inductive reactance applies only to sine waves because it
Increases with lower frequencies
Increases with lower inductance
Depends on the factor 2
Decreases with higher frequencies
An open resistor when checked with an ohmmeter reads
Zero
Infinite
High but within the tolerance
Low but not zero
Refers to the outward-curving distortion of the lines of force near the edges of two parallel metal plates that form a capacitor.
Skin effect
Night effect
Edge effect
Hall effect
A lead conductor has a resistance of 25 at 0 �C. Determine its resistance at -30 �C
Two complex numbers or phasors are said to be conjugate if they
Differ only in the algebraic sign of their quadratic components
Differ only in the algebraic sign of their real components
Are equal in their real and quadrature components including alge
Are equal in their real components but differ in their quadrature components i ncluding algebraic signs.
A law which states that when a constant electromotive force is applied to a circuit consisting of a resistor and capacitor connected in seriesa the time taken for the potential on the plates of the capacitor to rise to any given fraction of its final value depends only on the product of capacitance and resistance.
Child�s law
CR law
Coulomb�s law
Debye T3 law
The symbol Q refers to
Resonance quotient
Quality factor
Power quotient
Qualification test