If the capacitance of mica capacitor is 5 times the capacitcitora then the relative permittivity of mica is
Correct Answer :
B.
Related Questions
A coil of inductance L has an inductive reactance of XLin an ac circuit in which the effective current is I. The coil is made from a superconducting material. The rate at which power is dissipated in the coil is
I2XL
IXL
IXL2
An alloy composed of 84 % coppera 12 % manganese and 4 % nickel.
Manganin
Constantan
Nichrome
German silver wire
What does a capacitor store?
Voltage
Charge
Current
Power
For a triangular and sawtooth waveform the rms voltage or current equals
0.707times peak value
0.577 times peak value
0.577times average value
0.707times rms value
If two resistances of 9 and 6 are connected in parallela the total resistance is
When two complex conjugates are subtracteda the result is a
Quadrature component only
Complex component
In-phase component
Real component
The temperature coefficient of resistance of electrolytes is
Negative
Positive
Zero
Infinite
The reason why electrical appliances are connected in parallel.
It is a simple circuit
This makes the operation of appliances independent with each other
This results in reduced power consumption
All of the above
Which one of the following elements serves as a protection against overload?
Fuse
Switch
Resistor
Relay
Refers specifically to steady state values of quantities in ac circuits which are complex numbers.
Domain
Scalar quantity
Vector quantity
Phasor quantity
What is the most common non-sinusoidal waveform?
Square wave
Triangular wave
Trapezoidal wave
Sawtooth wave
Which of the following is not a factor affecting capacitance oor?
Area of plates
Number of plates
Distance between plates
Dielectric material used
The reciprocal of a complex number is
A complex number
A real number
An imaginary number
A whole number
In a complex resistance-reactance planea XLis represented
By an axis opposite the R axis
By an axis perpendicular to the XC axis
By an axis opposite the XCaxis
By an axis parallel to the R axis
The ratio between the active power and the apparent power of a load in an ac circuit is called
Quality factor
Power factor
Power ratio
Power reactive
A trimmer is a variable capacitor in which capacitance is varied by changing the
Number of plates
Dielectric
Distance between plates
Plate area
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.
Delta to wye or wye to delta transformation technique is applied to a ___ network.
One-terminal
Two-terminal
Three-terminal
Complex
Which of the following is not considered a physical factor affecting resistance?
Length
Material type
Temperature
Cross-sectional
A capacitor is used to
Block dc current
Pass dc current
Open voltage source
Short the voltage source
Liquids that are good conductors because of ionization are called
Electrolytic
Bases
Acid
Electrolytes
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
In an ac wavea 30 degrees of phase is ___ of a cycle.
½
According to Gauss theorema flux can be equated to
Charge
Field intensity
Current
Voltage
A capacitor of 0.5 F charged to 220 V is connected across an uncharged 0.5 F capacitor. What is the voltage across each capacitor?
220 V
150 V
110 V
22 V
An inductance of 1 mH is
0.001 H
0.01 H
0.0001 H
0.10 H
What is considered as the most important value of a sine wave?
Effective value
Peak value
Average value
Instantaneous value
An open inductor has
Zero resistance and infinite inductance
Infinite resistance and zero inductance
Infinite resistance and infinite inductance
Zero resistance and zero inductance
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
At what frequency will an inductor of 5mH have the same reactance as a capacitor of 0.1 F?
7.12 kHz
7.12 Hz
7.12MHz
7.12 GHz