The charging of a capacitor through a resistance obeys
Exponential law
Logarithmic law
Linear law
Square law
Correct Answer :
A. Exponential law
Related Questions
When the power factor of a circuit is zeroa
Power absorbed is maximum
Power absorbed is minimum
Power absorbed is zero
The impedance is minimum
The electric field strength between capacitor plates has a unit
Volts per meter
Volts per mil
Amperes per meter
Amperes per mil
Which of the following has negative temperature coefficient?
Carbon
Nickel
Brass
Constantan
Barium-strontium titanite dielectric material is also called
Ceramic
Polyster
Electrolytic
Bakelite
The power factor of a certain circuit in which the voltage lags behind the current is 80 %. To increase the power to 100 %a it is necessary to add ___ to the circuit.
Inductance
Capacitance
Resistance
Impedance
³Any resistance R in a branch of a network in which a current I is flowing can be replaced by a voltage equal to IR�. This states
Compensation theorem
Reciprocity theorem
Millman�s theorem
Superposition theorem
What value of R is needed with a 0.05 F Cfor an RCtime constant of 0.02 s?
400 M
400 G
400 k
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
Series resonance occurs when
XL= XC
XL= R
Z = R
Both A and C
Which of the following represents the energy stored in a cap
CV2/2
2Q2/C
C2/V
CV
The reactance curve is a plot of frequency versus _____ for a series RLCcircuit
Current
Voltage
Gain
Impedance
At parallel resonancea the currents flowing through L and C are
Infinite
Zero
Unequal
Equal
Which of the following capacitors has the highest cost per F?
Plastic
Air
Mica
Electrolytic
What is the rms value of a square wave?
Equals its peak value
Equals its peak-to-peak value
Peak divided by square root of two
Peak divided by pi
In adding or subtracting phasor quantitiesa ___ form is the most convenient.
Polar
Rectangular
Trigonometric
Exponential
The charging of a capacitor through a resistance obeys
Exponential law
Logarithmic law
Linear law
Square law
When two in-phase sine waves that have identical frequency and amplitude are added togethera then the result is a sine wave with ___ the amplitude of either.
Half
Twice
Four times
One-fourth
An inductive load always has a ___ power factor
Leading
Lagging
Zero
Unity
The unit of elastance is
Farad
Daraf
Siemen
Henry
Voltage resonance means
Series resonance
Parallel resonance
Current magnification
Gain magnification
For a carbon composition resistora typical resistance values range from
2.7 to 22 M
1000 to 10000
10 to 10 M
2.7 to 2.7G
What is the temperature coefficient of the resistance Eureka?
Infinity
Negative
Almost zero
Positive
Which is considered as the effect of a dielectric material?
Increasing capacitance
Decreasing capacitance
Reducing the working voltage
Increasing the distance between the plates
When voltage is applied across a ceramic dielectric the electrostatic field p roduced is 50 times greater than air dielectric. The dielectric constant of ceramic therefore is
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
A capacitor opposes change in
Voltage
Current
Voltage and current
Neither voltage nor current
If a multiplate capacitor has 10 platesa each of area 10 cm2a then
10 capacitors will be in parallel
10 capacitors will be in series
9 capacitors will be in parallel
9 capacitors will be in series
The hot resistance of an incandescent lamp is about ___ times its cold resistance.
Kirchhoff�s laws (KCL and KVL) are applicable to
DCcircuits
ACcircuits
DC as well as AC circuits
Passive networks alone