A-001-02: Electrostatic and electromagnetic fields, skin effect
A-001-02-01:
What is the result of skin effect?
As frequency increases, RF current flows in a thinner layer of the conductor, closer to the surface
As frequency decreases, RF current flows in a thinner layer of the conductor, closer to the surface
Thermal effects on the surface of the conductor increase impedance
Thermal effects on the surface of the conductor decrease impedance
A-001-02-02:
What effect causes most of an RF current to flow along the surface of a conductor?
Skin effect
Piezoelectric effect
Resonance effect
Layer effect
A-001-02-03:
Where does almost all RF current flow in a conductor?
Along the surface of the conductor
In a magnetic field in the centre of the conductor
In a magnetic field around the conductor
In the centre of the conductor
A-001-02-04:
Why does most of an RF current flow within a very thin layer under the conductor's surface?
Because of skin effect
Becasue the RF resistance of a conductor is much less than the DC resistance
Because a conductor has AC resistance due to self-inductance
Because of heating of the conductor's interior
A-001-02-05:
Why is the resistance of a conductor different for RF currents than for direct currents?
Because of skin effect
Because of the Hertzberg effect
Because conductors are non-linear devices
Because the insulation conducts current at high frequencies
A-001-02-06:
What unit measures the capacity to store electrical energy in an electrostatic field?
Farad
Coulomb
Watt
Volt
A-001-02-07:
What is an electromagnetic field?
The space around a conductor, through which a magnetic force acts
Current through the space around a permanent magnet
The force that drives current through a conductor
The current between the plates of a charged capacitor
A-001-02-08:
In what direction is the magnetic field oriented about a conductor in relation to the direction of electron flow?
In the direction determined by the left-hand rule
In all directions
In the same direction as the current
In the direct opposite to the current
A-001-02-09:
What is the term for energy that is stored in an electromagnetic or electrostatic field?
Potential energy
Kinetic energy
Ampere-joules
Joule-coulombs
A-001-02-10:
What is an electrostatic field?
The current between the plates of a charged capacitor
The space around a conductor, through which a magnetic force acts
Current through the space around a permanent magnet
The force that drives current through a conductor
A-001-02-11:
What unit measures the capacity to store electrical energy in an electromagnetic field?
Henry
Coulomb
Farad
Watt
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