JNTU B.Tech III ELECTROMAGNETIC THEORY AND TRANSMISSION LINES Previous Question Paper (August/September - 2024 - R16)

State Divergence theorem.

Mention the differences between scalar and vector magnetic potentials.

If the flux flowing through closed surface is 3 nc. What is the total charge enclosed by that surface?

State Maxwell's four laws in derivative form.

What is Brewster angle?

Find skin depth at 1GHz for copper having conductivity 5.7×10⁷ mho/m.

Define reflection coefficient and VSWR.

Find the input impedance of a section of a 50 Ω lossless transmission line that of length 0.1λ long and is terminated in a short circuit.

Draw typical stub matching transmission line.

List the applications of smith chart.

Derive Poisson's and Laplace's equations from fundamentals.

An infinitely long uniform line charge is located at y=3, z=5. If ρ_l = 30 nc/m, find field intensity at (i) origin (ii) P(5,6,1).

Develop an expression for potential due to dipoles.

Evaluate the electric field intensity at a point P (-5, 7, -4) in free space due to a charge of 0.2 milli coulombs placed at point R (0,0,0).

Distinguish between conduction and convection currents.

Find the polarization 'P' in a dielectric material with ε_r = 2.8 if D=3.0×10^-7 a_n c/m².

Derive the boundary conditions at the interface between (i) Dielectric-Dielectric (ii) Dielectric-conductor.

Derive Maxwell's equations in integral form. Based on this obtain the corresponding differential equation by applying Stroke's theorem.

Compare boundary conditions in Electrostatics and Magnetostatics.

Evaluate the reflection and transmission coefficients for the case of an electromagnetic wave in air incident normally upon the copper sheet at frequency of 1 MHz.

Find the energy stored in a standing wave incident normally on a perfect conductor over a distance -λ/4 to 0 per unit in x, y coordinates.

Show that for a uniform plane wave travelling in free space, in + Z direction, there is no E_z component.

How to differentiate conductors and insulators?

Discuss in brief about inductance loading of telephone cables.

A lossless transmission line of length 0.434 lambda and characteristic impedance 100 Ω is terminated in an impedance 260 + j 180 Ω. Find (i) Voltage reflection co-efficient (ii) Standing wave ratio (iii) Input Impedance.

The attenuation constant on a 50 ohm distortion less transmission line is 0.01 dB/m. The line has a capacitance of 0.1 nF/m. Find the resistance, inductance and conductance per meter of the line.

A loss less of 100 ohms is terminated by a load which produces SWR = 3. The first maximum is found to be occurring at 320 cm. If f = 300 MHz determine the load matching.

Explain the procedure for determining stub matching using Smith chart.

Sketch input impedance versus line length for short and open circuited line with line length less than λ/2.

Illustrate how impedance can be measured using Smith chart.

A line having ZO of 100 ohms is terminated into a load of 50 - j 50 ohms. It is desired to provide matching between the line and the load by means of a short circuit stub. Determine the length of the stub if signal frequency is 10 MHZ.