# Terms, Definitions, MCQs and Free Templates

## Practice and Learn everything. Definitions, MCQs, Tutorials, Solutions and Create your own Free Templates

In cell phone antennas are

The law J = σE, where J is current density, σ is electrical conductivity and E is field strength is

Purpose of antenna is

Antenna is a __________ element

Which of the following antennas is λ /4 length?

Which of the following is λ/2 length?

In a rectangular waveguide if operating frequency is greater than cut off frequency then propagation constant is

In a rectangular waveguide ZTE . ZTM is

A transmission line has characteristics impedance of (75 + j 0.01) Ω and is terminated in a load impedance of (70 + j 50) Ω. The reflection coefficient will be

A λ/8 section of transmission line is determined of load impedance of (2 – j 5) Ω. If characteristic impedance of line is 10 Ω. Then input impedance of line is

Whenever a wave is incident on a perfect conductor then the reflection coefficient is

A conductor carries 10 A current in + x direction and is lying in a field having a flux density 0.2 T directed along + z direction. The magnitude of force per metre length and direction are

Equipotential surfaces about a point charge are in which one of the following forms?

Which one of the following statement is correct?

A waveguide operated below cut off frequency can be used as

Unit of e is __________ .

ZL = 200 Ω and it is desired that Zi = 50 Ω The quarter wave transformer should have a characteristic impedance of

For TE or TM modes of propagation in bounded media, the phase velocity is

An electron in a homogeneous magnetic field and having velocity perpendicular to the direction of field moves

When a particular mode is excited in a waveguide, these appears an extra electric components in the direction of propagation. The resulting mode is

Ferromagnetic materials

The L/C has the dimension of

An electric charge Q is placed in a dielectric medium which of the following quantities are independent of the dielectric constant ε of the medium

The thin parallel wires are carrying current along the same direction. The force experienced by one due to the other is

Laplacian of a scalar function v is

A (75 – j 40) W load is connected to a co-axial line of z0 = 75ω at 6 MHz. The load matching on the line can be accomplished by connecting

Polystyrene has a relative permittivity of 2.7. If the wave is incident at an angle θi of 30° from air into polystyrene, the angle of transmission will be nearly

The cut off wavelength λc for TE20 mode for a standard rectangles waveguide is

The dimension of flux density is

A piece of copper and another piece of Germanium are cooled from 30°C to 80 K. The resistance of

For a hollow waveguide, the axial current must necessarily be

Consider the following; for a loss-less transmission line we can write, Zin = – jz0 for a shorted line with l = λ/8Zin = ± j ∞ for a shorted line with l = λ/4Zin= jz0 for an open line with l = λ/2Zin = 0 for a matched line of any length Select the […]

The current distribution along a travelling wave antenna can be written in the form

For a wave propagating in air filled rectangular waveguide.

It is desired to reduce the reflection at an air porcelain by use of 7/4 plate (for Porcelain μ = 40, and εr = 7). The thickness of the polystyrene plate required at 10 GHz will be

When the phase velocity of an EM wave depends on frequency in any medium, the phenomenon is called

A plane EM wave is travelling in an unbound loss less dielectric having μy = 1 and εy = 4, the time average Poynting vector of the wave is 5 W/m3 . The phase velocity vp (assuming velocity of light as 3 x 108 m/sec) is

When a plane wave is incident normally from dielectric ‘1’ (μ0, ε1) onto dielectric ‘2’ (μ0, ε2) the electric field of the transmitted wave is 2 times the electric field of the reflected wave. The ratio ε2/ε1 is

For an elliptically polarized wave incident on the interface of a dielectric at the Brewster angle the reflected wave will be

A rectangular waveguide (2.29 x 1.02) cm operates at a freq. of 11 GHz in TE10 mode. If the maximum potential gradient of the signal is 5 kV/cm, then the maximum power handling capacity of the waveguide will be