The resistance of an insulator ___ when its temperature is increased.
Decreases
Remains the same
Increases
Varies
Correct Answer :
A. Decreases
Related Questions
The Q-factor of a parallel resonant circuit is also known as
Voltage magnification factor
Current magnification factor
Gain magnification factor
Resonance magnification factor
Which of the following materials has the lowest dielectric strength?
Glass
Paper
Mica
Teflon
When two complex conjugates are subtracteda the result is a
Quadrature component only
Complex component
In-phase component
Real component
When capacitors are connected in parallela the total capacitance is
Greater than the largest capacitor
Smaller than the largest capacitor
Smaller than the smallest capacitor
Greater than the smallest capacitor
Tungsten filament of bulbs has a hot resistance higher than its cold resistance due to its temperature coefficient which is
Positive
Negative
Zero
Infinite
In a rectangular wavea the form factor is
A capacitor requires 12 C of charge to raise its potential of 3 V. What is the capacitance of the capacitor?
36 F
15 F
0.25 F
4 F
A series RL circuit has R of 10 and XL of 5 a its impedance in rectangular form is given by
10 +j 5
10 + j 10
10 ± j 5
10 ± j 10
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
Which of the following capacitors are used only in dc circuits?
Mica
Ceramic
Mylar
Electrolytic
Permeability is otherwise known as
Magnetic conductivity
Magnetic susceptibility
Electric conductivity
Electric susceptibility
What theorem is usually used in the analysis of transistor circuit?
Superposition theorem
Millman�s theorem
Thevenin�s theorem
Norton�s theorem
The ratio of the flux density to the electric field intensity in the dielectric is called
Permittivity
Field intensity
Permeability
Elasticity
What is the total effective capacitance of two 0.25 F capacitors connected in series?
0.125 F
1.25 F
0.50 F
2.5 if
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
The voltage lags the current by cycle in a
Purely resistive circuit
Purely inductive circuit
Purely capacitive circuit
Circuit containing resistancea capacitance and inductance
An inductor carries 2 A dc. If its inductance is 100 Ha then what is its inductive reactance?
Zero
1.3 k
The reciprocal of a complex number is
A complex number
A real number
An imaginary number
A whole number
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
Which of the following conditions is not true for a series RLCcircuit at resonance?
Z = jXL
XL= XC
The power factor is one
The magnitude of Z is
What is a closed path made of several branches of the network called?
Junction
Node
Terminal
Loop
A switch designed to have low capacitance between its terminal when open.
LOCAP switch
AntiLOCAP switch
Anticapacitance switch
Capacitance switch
The Q-factor of a parallel resonant circuit is also known as
Current magnification factor
Voltage magnification factor
Load factor
Leakage factor
What theorem is generally used in the analysis of vacuum tubes?
Superposition theorem
Millman�s theorem
Thevenin�s theorem
Norton�s theorem
A capacitor consists of two
Conductors only
Dielectric only
Conductors separated by a dielectric
Dielectric separated by a conductor
What is the resonant frequency of a circuit when L of 3 microhenrys and C of 40 picofarads are in series?
14.5 kHz
145 MHz
14.5 MHz
145 kHz
Another term for superconductor.
Generic conductor
Ultraconductor
Cryotron
Cryogenic conductor
A factor that states how much the resistance changes for a change in temperature?
Resistivity
Specific resistance
Coefficient of temperature change
Temperature coefficient of resistance
For a parallel ACcircuita ___ is used as a reference phasor.
Voltage
Power
Current
Resistance
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