(1) Define :
(a) The Scalar and Vector Magnetic Potential
(b) Magnetic flux density
(c) Current Density
(d) Surface Current density
(2) An infinitely long coaxial cable is carrying current I by the inner conductor of radius ‘a’
and – I by the outer conductor of radius ‘b’ and ‘c’. where c > b.
Deduce the expressions for H at
(i) < a (ii) a < < b (iii) b < < c (iv) > c.
Sketch plot of H as a function of radius.
a. The curl of the gradient of any scalar field is always the zero vector.
b. The divergence of the curl of any vector field A is always zero.
c. The Laplacian of a scalar field is the divergence of the gradient.
(4) State and explain Ampere’s circuital law. Find the magnetic field intensity due to
Long straight conductor using Ampere’s circuital law.
(5) State and explain Stokes’ Theorem.
(6) What is curl? Explain the physical interpretation of curl and state its application.
(7) A filamentry current of 20 A is directed in from infinity to origin on the positive Y axis,
and then back out to infinity along the positive X axis. Use Biot-savart law
to find H at P (0, 2, 0 )
(8) Find the magnetic field intensity at P(1, 2, 3) caused by curernt filament of 15 A in the ax
direction on X axis and extending from x=0 to 5.