1
GATE ECE 2012
+1
-0.3
A coaxial cable with an inner diameter of 1 mm and outer diameter of 2.4 mm is filled with a dielectric of relative permittivity 10.89. Given $${\mu _0} = \,4\,\pi \, \times \,{10^{ - 7}}$$
$$H/m,\,\,{\varepsilon _0} = {{{{10}^{ - 9}}\,} \over {36\,\pi }}\,F/m,$$ the characteristic impedance of the cable is
A
330 $$\Omega$$
B
100 $$\Omega$$
C
143.3 $$\Omega$$
D
15.9 $$\Omega$$
2
GATE ECE 2011
+1
-0.3
A transmission line of characteristic impedance 50 $$\Omega$$ is terminated by a 50 $$\Omega$$ load. When excited by a sinusoidal voltage source at 10 GHz, the phase difference between two points spaced 2 mm apart on the line is found to be $$\pi /4$$ radians. The phase velocity of the wave along the line is
A
$$0.8\,\, \times \,\,{10^8}\,m/s$$
B
$$1.2\,\, \times \,\,{10^8}\,m/s$$
C
$$1.6\,\, \times \,\,{10^8}\,m/s$$
D
$$3\,\, \times \,\,{10^8}\,m/s$$
3
GATE ECE 2010
+1
-0.3
A transmission line has a characteristic impedance of 50 $$\Omega$$ and a resistance of 0.1 $$\Omega$$/m. If the line is distortionless, the attenuation constant (in Np/m) is
A
500
B
5
C
0.014
D
0.002
4
GATE ECE 2010
+1
-0.3
If the scattering matrix [S] of a two port network is $$\left[ S \right] = \left[ {\matrix{ {0.2\,\angle \,\,{0^ \circ }} & {0.9\,\,\angle \,\,{{90}^ \circ }} \cr {0.9\,\angle \,\,{{90}^ \circ }} & {0.1\,\angle \,{{90}^ \circ }} \cr } } \right]$$\$ then the network is
A
lossless and reciprocal
B
lossless but not reciprocal
C
not lossless but reciprocal
D
neither lossless nor reciprocal
EXAM MAP
Medical
NEET