## Electromagnetic Engineering - May 2016

### MU Electronics Engineering (Semester 5)

Total marks: --

Total time: --
INSTRUCTIONS

(1) Assume appropriate data and state your reasons

(2) Marks are given to the right of every question

(3) Draw neat diagrams wherever necessary

### Attempt any four

**1(a)**Point charges Q

_{2}= 300 μC located at (2,-1,-3) m experiences a force ¯¯¯¯¯¯F2=8¯¯¯¯¯ax−8¯¯¯¯¯ay+4¯¯¯¯¯azN.F2¯=8ax¯−8ay¯+4az¯N. \displaystyle \overline {F_2}=8\overline {a_x}-8 \overline {a_y}+4\overline{a_z}N. due to point charges Q

_{1}at (3,-4,-2)m. Determine Q

_{1}. 5 marks

**1(b)** the height of a monopole antenna is &lambda
5 marks

**1(c)** State and explain Biot-Savart's law
5 marks

**1(d)** Find out the divergence and curl of the following function

¯¯¯¯F=2x2y¯¯¯ax+x2z¯¯¯ay+yz3¯¯¯azF¯=2x2ya¯x+x2za¯y+yz3a¯z \overline {F}=2x^2 y\overline {a}_x+x^2z\overline{a}_y+yz^3\overline{a}_z
5 marks

**2(a)** Derive Maxwells integral and point form of equations for static fields
5 marks

**2(b)** Find electric fields intensity E due to an infinite surface charge.
5 marks

**3(a)** Define the polarization of wave. Explain different types of polarization
5 marks

**3(b)** Derive boundary conditions for electric and magnetic fields at the boundary of two dielectric media.
5 marks

**4(a)** Explain in detail FDM method also state advantages and drawback of it.
5 marks

**4(b)** State Poynting theorem and derive the average poynting vector.
5 marks

**5(a)** Explain the significance of the term 'effective area of an antenna'. Derive the relationship between effective area and directivity of any antenna.
5 marks

**5(b)** Explain the principle modes of operation of helical antenna and draw its radiation pattern
5 marks

**6(a)** Classify anf explain different types of wave propagation.
5 marks

**6(b)** Explain folded dipole antenna and its applications.
5 marks

**6(c)** Explain following terms critical frequency, virtual height, maximum usable frequency
5 marks