# Quiz for the JUAS 2024 students – Electromagnetism

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Quiz for JUAS students 2024 - Electromagnetism

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The skin depth is:

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What is the order of magnitude of the quality factor Q in the superconducting Niobium cavities?

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How are the cavities fed?

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Applying the Stokes theorem, the two Faraday and Ampere-Maxwell law local form are (select both correct answers):

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In case of rectangular waveguides, how are the modes classified?

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Applying the Gauss-Ostrogradski theorem, the two Gauss laws in local forms are (select both correct answers):

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By applying the phasor definition, the time derivative is replaced by the factor

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What is the velocity of the electromagnetic waves in vacuum?

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The charge conservation principle states that the flux of current density through a closed surface is equal to:

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For the plane waves, there are two solutions representing two waves, they are:

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The Gauss law states that, given an arbitrary distribution of charge density inside the volume, the total amount of charge inside this volume is equal to

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The Faraday law states that the time variation of the magnetic induction flux through any open surface confined by a closed path is equal to:

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The Gauss law for the magnetic induction demonstrates that the flux of the magnetic induction through the volume surface is equal to:

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What happens below the cut-off frequency in a waveguide?

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Can the phase velocity , the velocity of the wave-front in the waveguide, be larger than the speed of light c?

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In particle accelerators, the resonant cavities are used to:

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In many applications of the coaxial cable, how much is the characteristic impedance?

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The Ampere Law states that the circulation of the magnetic field along a closed path equals the flux of current through any open surface confined by the closed path. Maxwell added a term to balance the equations that is: