GUJARAT TECHNOLOGICAL UNIVERSITYB.E. SemVth Examination December 2010Subject code: 151002 Subject Name: Engineering Electromagnetics Date: 15 /12 /2010 Time: 03.00 pm – 05.30 pm Total Marks: 70 Instructions:


Q.1 (a) Answer the following in brief

08 
(b) Answer the following

06 
Q.2 (a) Derive the electric field intensity and electric field density due to an infinite and uniform line charge density.  07 
(b) In the space, a line charge ρL=80 nC/m lies along the entire Zaxis, while point charge of 100 nC each are located at (1,0,0) and (0,1,0). Find the potential difference VPQ given P (2,1,0) and Q (3,2,5).

07 
OR
(b) Given the flux density D = (2cosθ/r3) ar + (sinθ/r3) aθ c/m2, evaluate both sides of the divergence theorem for the region defined by 1˂ r ˂ 2 , 0 ˂ θ ˂ π/2 , 0˂ ɸ˂ π/2 
07 
Q.3 (a) Describe the boundary condition between free space and conductor. What is an importance of boundary condition?  07 
(b) Write Maxwell’s equations in point form and explain physical significance of equations.  07 
OR
Q.3 (a) Derive Poisson’s and Laplace’s equations and states their applications. 
07 
(b) Write Maxwell’s equations in integral form and explain their physical significance.  07 
Q.4 (a) State and explain Ampere’s circuital law. Find the magnetic field intensity due to long straight conductor using Ampere’s circuital law.  07 
(b) A charge of 10 nC is moving with a velocity of 107(0.5 ax + ay 0.71 az) m/s. Determine the force exerted on the test charge when

07 
OR
Q.4 (a) What is curl? With help of curl meter explain the physical interpretation of curl and state its applications. 
07 
(b) A filamentary current of 10 A is directed in from infinity to the origin on the positive x axis, and then back to infinity along the positive y axis. Use the Biot Savart law to find H at P (0,0,1)  07 
Q.5 (a) Define and explain the following terms:

07 
(b) Write short note on:

07 
Or
Q.5 (a) Define and explain the following terms:

07 
(b) (i) Transform the 5ax vector to spherical coordinate at A(x = 2,y = 3, z = 1).
(ii) Given V = (10/r2 ) sinθcosɸ, Find the electric flux density at (2, π/2,0) 
07 