Electromagnetic waves are produced by the simultaneous vibration of electric and magnetic fields and can travel through space without a medium. They have various properties including being transverse waves, obeying the wave equation relating frequency, wavelength and speed, and maintaining frequency but changing speed and wavelength when passing between media. Electromagnetic waves have many applications from gamma rays being used in cancer treatment to visible light in fiber optics, X-rays for medical imaging, ultraviolet for sterilization, microwaves for communication and analysis, and radio waves for radio, television, radar and navigation.

2. INTRODUCTION
Objectives
 Components of EM waves
 Properties of EM waves
 Role of EM waves and their applications

3. Electromagnetic Wave
Produced by simultaneous vibration of Electric Field
Magnetic field

4. Wavelength of electromagnetic spectrum

5. Properties of EM wave
1. EM waves are transverse wave.
2. Do not require any medium for travel.
3. Travel at speed of 3x108 ms-1 in
vacuum.
4. Can be reflected
or refracted.

6. 5. All EM wave obeys the wave equation.
v =f x λ
Where v = speed of wave (m/s)
f = frequency of wave (Hz)
λ = wavelength (m)
6. Their frequencies do not change as they pass
from one medium to another.
But their speed and wavelength will change.

7. Applications
Gamma rays :
 It can cause serious illness due to
great penetrating ability.
 when used in controlled conditions,
gamma rays is useful in cancer
treatment.
Visible Light
 Used in optical fibres and
telecommunications

8. X-rays :
• diagnostic tool in
dentistry and
medicine
• at airports inspect
the content of your
luggage
• used to find cracks
in structures

9. Ultra-violet :
• used in hospitals to
sterilize the surgical
instruments
• Operation theatres as it
kills bacteria and viruses
Microwaves :
• Analysis of fine details of
molecular and atomic structure
• Telephone communication

10. Radio waves :
 Radio and television
communication
 Radar & satellite communication
 Navigation or ships & aircrafts

11. Thank you