Velocity factor, effect of line terminated in non-characteristic impedance

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A-007-02: Velocity factor, effect of line terminated in non-characteristic impedance

A-007-02-01:
What kind of impedance does a quarter wavelength transmission line present to the source when the line is shorted at the far end?

A very high impedance

The same as the characteristic impedance of the transmission line

The same as the output impedance of the source

A very low impedance

A-007-02-02:
What kind of impedance does a quarter wavelength transmission line present to the source if the line is open at the far end?

A very low impedance

A very high impedance

The same as the output impedance of the source

The same as the characteristic impedance of the transmission line

A-007-02-03:
What kind of impedance does a half wavelength transmission line present to the source when the line is open at the far end?

A very high impedance

The same as the characteristic impedance of the transmission line

The same as the output impedance of the source

A very low impedance

A-007-02-04:
What kind of impedance does a half wavelength transmission line present to the source when the line is shorted at the far end?

A very low impedance

A very high impedance

The same as the characteristic impedance of the transmission line

The same as the output impedance of the source

A-007-02-05:
What is the velocity factor of a transmission line?

The velocity of the wave on the transmission line divided by the velocity of light

The velocity of the wave on the transmission line multiplied by the velocity of light in a vacuum

The index of shielding for coaxial cable

The ratio of the characteristic impedance of the line to the terminating impedance

A-007-02-06:
What is the term for the ratio of the actual velocity at which a signal travels through a transmission line to the speed of light in a vacuum?

Velocity factor

Characteristic impedance

Surge impedance

Standing wave ratio

A-007-02-07:
What is a typical velocity factor for coaxial cable with polyethylene dielectric?

0.66

0.33

0.1

2.7

A-007-02-08:
What determines the velocity factor in a transmission line?

Dielectrics in the line

The line length

The centre conductor resistivity

The terminal impedance

A-007-02-09:
Why is the physical length of a coaxial cable shorter than its electrical length?

RF energy moves slower along the coaxial cable than in air

The surge impedance is higher in the parallel feed line

Skin effect is less pronounced in the coaxial cable

The characteristic impedance is higher in a parallel feed line

A-007-02-10:
The reciprocal of the square root of the dielectric constant of the material used to separate the conductors in a transmission line gives the ____________ of the line:

velocity factor

VSWR

impedance

hermetic losses

A-007-02-11:
The velocity factor of a transmission line is the:

ratio of the velocity of propagation in the transmission line to the velocity of propagation in free space

impedance of the line, e.g. 50 ohm, 75 ohm, etc.

speed at which the signal travels in free space

speed to which the standing waves are reflected back to the transmitter