EC3452 Electromagnetic Fields
Important Questions
Unit 1
- Analyze the Gradient of scalar and divergence and curl of the vector.
- Find the gradient of the scalar fields U = x ^ 2 * y + xyz and U = e ^ (- x) * sin 2x * cos y .
- Convert points P(1, 3, 5) and T(0, – 4, 3) from Cartesian to cylindrical and Spherical coordinates.
- Given, A=(sin2p) ao in cylindrical co-ordinates. Find curl of A at (2, π/4,0).
- Given the two points, A(x = 2, y = 3, z=1) and B=(r=2,0 = 20°, φ = 220°). Find
(i) Spherical co-ordinates of A
(ii) Cartesian co-ordinate of B.
Unit 2
- A charge is distributed on x axis of Cartesian system having a line charge density of 3 X² µC/m. Find the total charge over the length of 10 m.
- If D= (2y ^ 2 + z) vec a x +4xy vec a y +x vec a z C/m^ 2 find
(1) The volume charge density is at (-1, 0, 3).
(2) The flux through the cube is defined 0 <= x <= 1 0 <= y <= 1 0 <= z <= 1 by
(3) The cube encloses the total charge. - Rearrange Gauss’s law and develop Laplace’s and Poisson’s equations.
- Interpret the Electric Flux density for a uniformly charged sphere of radius ‘a’. Construct a Gaussian surface for the case of r >= a and r <= a separately.
- A parallel-plate capacitor has a plate area of 200m ^ 2 and a plate separation of 3 cm. The charge density is with air dielectric. Determine (1) The capacitance of the capacitor.
(2) The voltage between the plates - If V=x-y+xy+2z V, Find
(i) E at (2, 2, 1)
(ii) Energy stored in a cube of side 1m centered at the origin.
Unit 3
- Prove that total magnetic field intensity (H) outside of the outer coaxial conductor is zero for infinitely long coaxial transmission line using Amperes law. Determine H at each Amperian path.
- Determine the Magnetic field and current distributions for the following three conditions
(i) Infinite line current along the z-axis
(ii) Infinite sheet of current
(iii) Infinitely long coaxial transmission line - Obtain the expression for magnetic field intensity on an axis of a circular ring.
- Find the magnetic field intensity at a point P, due to a finite straight conductor, carrying a current I.
Unit 4
- A thin ring of radius 5 cm is placed on plane z1 cm so that its center is at (0, 0, 1) cm. If the ring carries 50 mA a,, find H at (0, 0, 1) cm and (0, 0, 10)cm.
- Prove that Maxwell’s equations are related to time-varying magnetic fields.
- Reconstruct Ampere’s circuit law for time-varying situations to satisfy Faraday’s law.
- Derive the Helmholtz’s wave equations for both E and H fields.
- Derive wave equation, and explain the properties of uniform plane waves in free space.
- Derive and explain, Maxwell’s equations both in integral and point forms.
Unit 5
- Conclude that the tangential components of H are discontinuous across the boundary, and the normal components of H are continuous across the dielectric-dielectric boundary medium. Besides, determine H’s tangential and normal components across the dielectric-conductor boundary medium.
- A uniform plane wave propagating in a lossless medium has E=2sin[108t-ßz]ä, V/m. If 6,1, μ, = 2 and σ=-3V/m, characterize the medium. Compute the nẞ and H.
- If the wave encounters a perfectly conducting plate normal to the z-axis at z=0, find the reflected wave E, and H,.
- Derive pointing vector in integral and point form from Maxwell’s equation.
- Explain the reflection of plane wave by conducting medium, under normal incidence.