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
Correct Answer :
B. Power factor
Related Questions
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Gain magnification factor
Resonance magnification factor
A capacitance of 6 ��F means
6 pF
6 nF
6 fF
6 aF
Rationalizing the denominator of a complex number means
Eliminating the j component in the denominator
Adding j component in the denominator
Eliminating the j component in the numerator
Adding j component in the numerator
Which one of the following elements serves as a protection against overload?
Fuse
Switch
Resistor
Relay
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 the total resistance of a two equal valued resistors in series?
The difference of both
The product of both
Twice as one
The sum of their reciprocals
The charging of a capacitor through a resistance follows what law?
Linear law
Hyperbolic law
Inverse-square law
Exponential law
If the inductance is decreaseda the impedance of the circuit containing a resistor a capacitor and an inductor connected in series to an ac source
Decreases
Increases
Decreases or increases
Decreasesa increases or remains the same
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Resistor
Inductor
Capacitor
Transistor
In an ac circuit with inductive reactance ?, the
Phase angle of the circuit is always 45�
Voltage across the inductance must be 90� out o f-phase witht he applied voltage
Current through the inductance lags its induced voltage by 90�
Current through the inductance and voltage across it are180� outof-phase
How many degrees of phase represents one full cycle?
The voltage lags the current by cycle in a
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Purely inductive circuit
Purely capacitive circuit
Circuit containing resistancea capacitance and inductance
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
When resistance are connected in parallela the total resistance is
Less than the smallest resistance in the connection
Greater than the smallest resistance in the connection
Between the smallest and greatest resistance in the connection
Increasing and decreasing depending upon the supply voltage
In an RL series circuita
Current lags voltage by less than 90�
Current lags voltage by 180�
Current lags voltage by 90�
Current leads voltage by 90�
A resistor wound with a wire doubled back on itself to reduce the inductance.
Bifilar resistor
Wire-wound resistor
Anti-inductive resistor
Bleeder resistor
A real current source has
Infinite internal resistance
Zero internal resistance
Large internal resistance
Small internal resistance
What is the reciprocal of quality factor?
Power factor
Reactive factor
Dissipation factor
1/Q factor
In a complex number 5 + j 10a 10 is called ___ part.
Imaginary
Real
Conjugate
Integer
What determines the magnitude of electric current?
The rate at which electrons are produced
The type of material used
The current carrying capacity of the circuit
The rate at which electrons pass a given point
VL= VCin a series RLCcircuit when
The value of the impedance is minimum
The power factor is zero
The current leads the total voltage by 90�
The total voltage is zero
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
What is the specific resistance of a pure silicon?
55 -mm
55 -m
55 -cm
55 k -m
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Increased
The same
Decreased
Variable
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Bisects
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Is less than
Is equal to
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V(m)2
V(m)
V/m2
V/m
When the temperature of copper wire is increased its resistance is
Increased
Decreased
Constant
Zero
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Polar
Rectangular
Trigonometric
Exponential
Refers specifically to steady state values of quantities in ac circuits which are complex numbers.
Domain
Scalar quantity
Vector quantity
Phasor quantity
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