CORPORATE INSTITUTE OF SCIENCE AND TECHNOLOGY
DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGG
IMP QUESTIONS FOR PUT (Nov 2015)
Sub- EMT(EX-302)
UNIT-I
1. Define following- (a) Gradient (b) Curl (c) Divergence (d) Intensity of electric field (e) Electric flux
density (f) Electric potential and potential difference.
2.Find the gradient of following function:
f(x,y,z) = 20 e—x Sin(πy/6)
3.Verify that vector field
A = yz ax+ zx ay + xy az is irrotational and solenoidal.
4. Determine D at (4, 0, 3) if there is a point charge 5mC at (4, 0, 0) and a line charge
3(mC/m) along y-axis
6. State and prove following- (a) Divergence theorem (b) Stokes theorem.
7. State coulomb’s law.
8 .Derive an expression for intensity of electric field due to an uniformly charged line.
9. Derive an expression for intensity of electric field due to an uniformly charged circular disc.
10 State and prove Gauss’s law. What are the applications of Gauss’s law.
UNIT-II
1. What is an electric dipole? Derive an expression for potential and electric field due to a dipole.
2. Define dipole moment .
3.. Derive Laplace’s and poisson’s equations. What is the significance of these equations?
4. Derive the boundary conditions for electric field at the boundary of two dielectrics.
5. Write a short note on image theory.
6. What is energy density? Derive an expression for energy density.
7.Given a potential field V=50xyz in free space. Find the total energy stored within the cube 0< x,y,z< 2
8. Derive Equation of continuity .
9. Define following : (a) conduction current density (b) displacement current density.
UNIT-III
1.
State and explain Biot-savart’s law.
2. By using Biot-savert’s law derive an expression for intensity of magnetic field –(a) at a point due to a
straight current carrying conductor (b) at a point located at the axis of a circular current carrying loop.
3. State and explain Ampere’s law.
4. Derive point form of Amperes law.
5. A circular loop of radius 4m carry a d.c. current of 10 amp. Determine intensity of magnetic field at
centre of loop.
6. By using Ampere’s law derive an expression for intensity of magnetic field –
(a) Due to a current carrying sheet.
(b) Due to a current carrying solenoid at the axis of solenoid.
(c) Due to a co-axial cable at all points located inside and outside of cable.
7. Define inductance ? Derive formula for inductance of a (a) cylindrical solenoid (b) toroid.
8. Derive an expression for force between two parallel current carrying conductors.
9. Derive boundary conditions for magnetic field at the boundary of two magnetic materials.
UNIT-IV
1. State and explain Faraday’s law.
2. Define self and mutual inductance .
3. Write Maxwell’s equations in integral form and differential form (point form) also give their word
statement.
4. Write Maxwell’s equations for time varying fields (time harmonic fields).
5. Derive poynting vector theorem. Also write expressions for instantaneous, average and complex
pointing vector
6. Derive an expression for inductance of (a) solenoid (b) Toroid
7. Derive an expression of mutual inductance between a straight long wire and asquare loop .
8. A solenoid with 2000 turns is 300mm long and with 20mm diameter. If the current in the solenoid is
600mA, find the inductance of the solenoid.
9. For a lossy dielectric, σ =5 S/m, and ɛr= 1, The electric field intensity is E=100sin1010t. Find JC and
JD.
10. Given E=Emsin(ωt-βz) ay in free space, find intensity of magnetic field .
UNIT-V
1. Derive three dimensional Helmholtz’s wave equation in free space.
2. What is intrinsic impedance?
3. Magnetic field intensity of a uniform plane wave in air is 20 A/m in the ay Direction. The wave is
propagating in ay direction at a frequency of 2 x 109rad/ sec. Find
(I ) Wavelength (ii) frequency (iii) intensity of electric field.
4. Define polarization of a wave. Also define circular, elliptical and linear polarization
5. Derive pointing vector theorem .
6. The equation for the uniform plane wave travelling in free space is given by
Ey=10.4Cos(2πx109t- βx) µV/m, find (a) Direction of propagation of wave (b) velocity of
propagation (c) phase constent (d) expression for magnetic field.
7
If E = 200 e(4x – kt) ay (V/m) in free space. Use Maxwell’s equation to find k and H.
8.Define coefficient of transmission and coefficient of reflection.
9. Derive an expression for coefficient of transmission and reflection for an EM wave incident
normally on a dielectric-dielectric boundry