The terminology of different parts of the electromagnetic spectrum is given in the text. Use the formula E = hν (for energy of a quantum of radiation: photon) and obtain the photon energy in units of eV for different parts of the electromagnetic spectrum. In what way are the different scales of photon energies that you obtain related to the sources of electromagnetic radiation?

Sea water at frequency v = 4 × 108 Hz has permittivity ε ≈ 80 ε_o, permeability μ ≈ μo and resistivity ρ = 0.25 Ω–m. Imagine a parallel plate capacitor immersed in sea water and driven by an alternating voltage source. What fraction of the conduction current density is the displacement current density?

Displacement current goes through the gap between the plates of a capacitor when the charge of the capacitor

A long straight cable of length l is placed symmetrically along z-axis and has radius a(<<l). The cable consists of a thin wire and a co-axial conducting tube. An alternating current flows down the central thin wire and returns along the co-axial conducting tube. The induced electric field at a distance s from the wire inside the cable is

(i) Calculate the displacement current density inside the cable.

(ii) Integrate the displacement current density across the cross section of the cable to find the total displacement current Id.

(iii) Compare the conduction current I₀ with the displacement current .

You are given a 2μF parallel plate capacitor. How would you establish an instantaneous displacement current of 1mA in the space between its plates?

Using B = μ₀ H find the ratio E₀/H₀ for a plane electromagnetic wave propagating through vacuum. Show that is has the dimensions of electric resistance. This ratio is a universal constant called the impedance of free space.

A plane EM wave travelling along z direction is described by and . Show that

(i) The average energy density of the wave is given by .

(ii) The time averaged intensity of the wave is given by .

A plane EM wave travelling in vacuum along z direction is given by and

(i) Evaluate over the rectangular loop 1234 shown in Fig 8.2.

(ii) Evaluate over the surface bounded by loop 1234.

(iii) Use equation to prove .

(iv) By using similar process and the equation , prove that

A variable frequency ac source is connected to a capacitor. How will the displacement current change with decrease in frequency?

You are given a 2μF parallel plate capacitor. How would you establish an instantaneous displacement current of 1mA in the space between its plates?