Which of the following does not affect resistance?
Resistivity
Cross-sectional area
Mass
Length
Correct Answer :
C. Mass
Related Questions
What is a closed path made of several branches of the network called?
Junction
Node
Terminal
Loop
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Ohm�s law
Coulomb�s law
Kirchhoff�s first law
Kirchhoff�s second law
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Temperature
Voltage
Skin effect
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The result of rust in electrical (wire) connection is
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Near the final maximum value of current
At midvalue of current
At half-power points
After one time constant
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300 pF
100 pF
50 pF
33.3 pF
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43a000
54a321
The distance between the capacitor plates increases two timesa then its capacitance
Increases two times
Increases four times
Decreases two times
Decreases four times
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Open voltage source
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Smith chart
Reactance chart
Impedance chart
Resonance chart
If a coil has a Q of 10a it means that
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The energy wasted in its resistance is 10 times the energy stored in the magnetic field of the coil
It is a low Q coil
It is a high Q coil
Which one of the following elements serves as a protection against overload?
Fuse
Switch
Resistor
Relay
The power factor of a circuit is equal to
RZ
XC/Z
XL/Z
R/Z
Which of the following capacitors has the highest cost per F?
Plastic
Air
Mica
Electrolytic
Which of the following is not considered a physical factor affecting resistance?
Length
Material type
Temperature
Cross-sectional
The mutual inductance between two coils is ___ the reluctance of magnetic path.
Directly proportional to
Inversely proportional to
Independent to
Equal to
At what frequency will the current in a series RLCcircuit reach its maximum value for an applied voltage of 15 V with R = 500 a L = 100 H and C= 0.001 F?
503 kHz
403 kHz
603 kHz
303 kHz
The internal resistance of an ideal current source is
Infinite
Zero
Equal to the load resistance
To be determined
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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
What is the purpose of a load in an electric circuit?
To increase the circuit current
To decrease the circuit current
To utilize electrical energy
To make the circuit complete
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
A tank circuit is a
Parallel LC circuit
Series LCcircuit
A resonant circuit
A non-resonant circuit
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Moving the coils closer
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Carbon
Nickel
Brass
Constantan
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Current
Voltage
Both current and voltage
Neither current nor voltage
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Increase the power rating compared with one resistor alone
Increase the voltage rating compared with one resistor alone
Reduce the voltage rating compared with resistor alone
Result in an expensive circuit
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0 + j 300
300 + j 90
0 ± j 300
300 +j 0
If resonant frequency is 10 kHz and quality factor is 50a then
Bandwidth is 200 Hz
XL= is 50a000
R is 50
XC= is 50a000
Which of the following does not affect resistance?
Resistivity
Cross-sectional area
Mass
Length
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