The radius of the wire in a coaxial cable is 0.65 mm and the inner radius of the coaxial conducting cylinder is 1.45 mm. Assuming that there is vacuum between the

wire and the cylinder, calculate the capacitance of a 1.5 m length of the cable.

What is the difference between ohmic conductor and non-ohmic conductor? Give

one example each and draw their IV characteristic curves.

An electron and a proton, moving with equal velocity, enter a region of uniform, perpendicular magnetic field. Calculate the ratio of the radii of their circular paths in

the field.

Using Maxwell’s equations in free space, derive the wave equation for the

electric field vector. Obtain the conditions under which the following time varying electric and magnetic fields satisfy Maxwell’s equations in vacuum with no source charges or currents:

E = kˆ E0 sin ( y − vt)

B = ˆi B0 sin ( y − vt)

where E₀ and B₀ are constant.

The line density of charge in a wire is 0.2 Cm⁻¹. If this wire is symmetrically enclosed, along its length, by a cylindrical surface of radius 1 m and length 1.5 m, calculate i) the electric flux through the cylindrical surface, and ii) the electric field

at the curved surface of the cylinder.

A positive 20µC charge is placed at the centre of a circle of radius 20 cm. If we move a positive 2µC charge once along the circumference of the circle, will any work be done in the process? Justify your answer

Show that, if there are any unbalanced, static charges on an isolated conductor, they

must reside on its surface.