Suppose that the electric field part of an electromagnetic wave in vacuum is 
E = [3.1 cos{1.8 y + (5.4 \(\times\)10⁶t)}] \(\hat{i}\)
(i) What is the direction of propagation?
(ii) What is the wavelength \(\lambda \)?
(iii) What is the frequency \(v\) ?
(iv) What is the amplitude of the magnetic field part of the wave?
(v) Write an expression for the magnetic field part of the wave.

About 5% of the power of a 100 W light bulb is converted to visible radiation. What is the average intensity of visible radiation.
(a) At a distance of 1 m from the bulb
(b) At a distance of 10 m?
Assume that the radiation is emitted isotropically and neglect reflection.

Monica's mother was heating food on a gas stove. Her friend Ruchi came and saw her mother heating food on the gas stove. Ruchi told Monica's mother, "Why don't you buy a microwave oven"? Monica's mother replied at once that she doesn't like to use microwave oven. Monica and Ruchi made it clear that microwave is not harmful for cooking food. This is an easy and safe process. Monica's mother got convinced and ordered for a microwave oven. Monica's mother then arranged a small party for her friends and told them the advantages of a microwave oven.
What value was displayed by Monica and her friend?
What value was displayed by Monica to her friends?

The amplitude of the magnetic field part of a harmonic electromagnetic wave in vacuum is B₀ = 510 nT. What is the amplitude of the electric field part of the wave?

Use the formula \({ \lambda }_{ m }\) T = 0.29 cm-K to obtain the characteristic temperature ranges for different parts of the electromagnetic spectrum. What do the numbers that you obtain, tell you?

In a plane electromagnetic wave, the electric field oscillates with amplitude \(20V{ m }^{ -1 }\). Find (a) energy density of electric field (b) energy density of magnetic field

If the wavefront of electromagnetic wave travelling in a vacuum is given by; \(\overset { \rightarrow }{ r } =\hat { i } +\hat { j } +\hat { k } \) find the angle made by the direction of propagation of e.m. wave with the y-axis.

What features of e.m. waves led maxwell to conclude that light itself is e.m. wave?

What ideas led maxwell to think about electromagnetic waves?

The electric field of a plane e.m.wave in vacuum is represented by; \(\overset { \rightarrow }{ { E }_{ x } } =0\)
\(\overset { \rightarrow }{ { E }_{ y } } =0.5cos\left[ 2\pi \times { 10 }^{ 8 }\left( t-\frac { x }{ c } \right) \right] ;\ \overset { \rightarrow }{ { E }_{ 2 } } =0\)
(a) What is the direction of propagation of electromagnetic waves?
(b) Determine the wavelength of the wave.
(c) Compute the component of the associated magnetic field.

Electromagnetic waves travel in a medium with a speed of 2 x 10⁸ ms^-1. The relative magnetic permeability of the medium is 1. Find the relative electrical permittivity.

Show that average value of radiant flux density S over a single period T is given by \(S=\frac { 1 }{ { 2c\mu }_{ 0 } } { E }_{ 0 }^{ 2 }.\)

Identify the type of waves which are produced by the following way and write one application for each:
(i) Radioactive decay of the nucleus.
(ii) Rapid acceleration and decelerations of electrons in aerials.
(iii) Bombarding a metal target by high energy electrons.