In a travelling-wave tube, the phase velocity of the axial component of the rf field on the slow-wave structure is kept:

Slightly more than the velocity of electrons

Equal to the velocity of the electrons

Slightly less than the velocity of electrons

Slightly more than the velocity of electrons

Equal to the velocity of light in free space

In a travelling-wave tube, the phase velocity of the axial component o

1.	In a travelling-wave tube, the phase velocity of the axial component of the rf field on the slow-wave structure is kept:
A.	Equal to the velocity of the electrons
B.	Slightly less than the velocity of electrons
C.	Slightly more than the velocity of electrons
D.	Equal to the velocity of light in free space
Answer» C. Slightly more than the velocity of electrons

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In a travelling-wave tube, the phase velocity of the axial component of the rf field on the slow-wave structure is kept:

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