The decreasing order of wavelength of infrared, microwave, ultraviolet and gamma rays is:

1.	gamma rays, ultraviolet, infrared, microwaves.
2.	microwaves, gamma rays, infrared, ultraviolet.
3.	infrared, microwave, ultraviolet, gamma rays.
4.	microwave, infrared, ultraviolet, gamma rays.

Which of the following statement is false for the properties of electromagnetic waves?

The velocity of electromagnetic radiation in a medium of permittivity ${\epsilon }_0$ and permeability ${\mu }_0$ is given by:

1.  $\sqrt{\frac{{\mathrm{\epsilon }}_{\mathrm{o}}}{{\mathrm{\mu }}_{\mathrm{o}}}}$

2.  $\sqrt{{\mathrm{\mu }}_{\mathrm{o}}{\mathrm{\epsilon }}_{\mathrm{o}}}$

3.  $\frac{1}{\sqrt{{\mathrm{\mu }}_{\mathrm{o}}{\mathrm{\epsilon }}_{\mathrm{o}}}}$

4.  $\sqrt{\frac{{\mathrm{\mu }}_{\mathrm{o}}}{{\mathrm{\epsilon }}_{\mathrm{o}}}}$

The electric and magnetic fields of an electromagnetic wave are:

Which colour of the light has the longest wavelength?

A parallel plate capacitor of capacitance \(20~\mu\text{F}\) is being charged by a voltage source whose potential is changing at the rate of \(3~\text{V/s}.\) The conduction current through the connecting wires, and the displacement current through the plates of the capacitor would be, respectively:
1. zero, zero
2. zero, \(60~\mu\text{A}\)
3. \(60~\mu\text{A},\) \(60~\mu\text{A}\)
4. \(60~\mu\text{A},\) zero

The electric and the magnetic fields, associated with an electromagnetic wave, propagating along the positive Z-axis, can be represented by:
1. \(\left [E=E_{0}\hat{k},~B=B_{0}\hat{i} \right ]\)
2. \(\left [E=E_{0}\hat{j},~B=B_{0}\hat{j} \right ]\)
3. \(\left [E=E_{0}\hat{j},~B=B_{0}\hat{k} \right ]\)
4. \(\left [E=E_{0}\hat{i},~B=B_{0}\hat{j} \right ]\)

The condition under which a microwave oven heats up a food item containing water molecules most efficiently is: