Question 121. 2. A cavity resonator can be represented by

Question 122. 1. A rectangular waveguide 2.29cm x 1.02 cm operates at a frequency of 11 GHz in TElo mode. If the maximum potential gradient of thesignal is 5 kV/cm, then the maximum power handling capacity of the waveguide will be

Question 123. 5. The degenerate modes in a waveguide are characterised by

Question 124. 4. In an air line, adjacent maxima are found at 12.5 cm and 37.5 cm. The operating frequency is

Question 125. 6. For TM waves in a parallel plate waveguide, the minimum attenuation arising from imperfect conductors would occur at a frequency of (fc is the cut-off frequency)

Question 126. 3. The cut-off wavelength Xc for TE20 mode for a standdrd rectangular waveguide is

Question 127. 9.  A circuilar air filled waveguide of radius 5 cm is operated in the THoi mode. The waveguide is then completely filled with a dielectric of relative permittivity 2.25 and relative permeability 1.0. The cut-off wavelength for the THoi mode is 0.082 m when the waveguide is air-filled.When the waveguide is filled with the dielectric, the cut-off frequency will become nearly

Question 128. 7. For a rectangular waveguide (a x b, a> b) to suport only the TE10 mode at wave length which one of the following pairs of inequalities is to be satisfied?

Question 129. 8. In a hollow rectangular waveguide, the phase velocity

Question 130. 1. Which one of the following statements is true for electro-magnetic wave propagation through a rectangular waveguide of cross section 2a x a?