The electromagnetic spectrum consists of all types of electromagnetic waves, ranging from radio waves to gamma rays. The properties of electromagnetic waves include speed, frequency, and wavelength, with speed being equal to frequency multiplied by wavelength. Shorter wavelengths have higher frequencies and energies, while longer wavelengths have lower frequencies and energies. The electromagnetic spectrum includes radio waves, microwaves, infrared waves, visible light, ultraviolet waves, X-rays, and gamma rays, which have various applications such as communication, heating, vision, sterilization, and medical imaging.

1. The Electromagnetic
Spectrum

2. What is the Electromagnetic Spectrum
• The electromagnetic spectrum is the complete spectrum (or continuum) of all
forms of “light”
• An electromagnetic wave consist of electric and magnetic fields which vibrate –
thus making waves.

3. The Electromagnetic spectrum consist of:
• Radio waves
• Microwaves
• Infrared waves
• Visible light waves
• X-rays
• Gamma rays

4. Waves
• Properties of electromagnetic waves include speed, frequency and wavelength.
• Speed (s), frequency (f) and wavelength (λ) are related in the formula:
s = f x λ
• All light travel at a speed of 3 𝑥 108
m/s in a vacuum.

5. Wavelength, Frequency, Energy
• Electromagnetic wave characteristics:
 Short wavelengths have a high frequency
 Long wavelengths have a low frequency
• Electromagnetic waves and Energy:
 High frequency waves have high energy
 Low frequency waves have low energy

6. Wavelength, Frequency, Energy
Fill in the table below:
wavelength frequency energy
long
high

7. Types of Electromagnetic Waves

8. Microwaves
• Longer than radio, shorter than infrared or
visible light.
• Used for communication, medicine and
consumer use (microwave ovens).

9. Radio waves
• Low energy waves with long wavelengths
• Includes FM, AM, radar, and TV waves
• Low frequency

10. Infrared waves
• Invisible electromagnetic waves that are detected
as heat.
• Can be detected with special devices.
• Higher energy than microwaves but lower than
visible light.

11. Visible light
• The portion of the electromagnetic spectrum that
human eyes can detect.
• ROY G BIV (red, orange, yellow, green, blue,
indigo and violet)

12. Ultraviolet waves
• Higher energy than light waves
• Can cause skin cancer and blindness in human.
• Used in tanning beds and sterilizing equipment.

13. X-rays
• High energy waves
• Used in medicine, industry and astronomy.
• Can cause cancer

14. Gamma rays
• Highest energy
• Blocked from Earth’s surface by atmosphere.

15. EM WAVE
CHARACTERISTICS
OF EM WAVE
APPLICATION OF EM
WAVE
Radio Waves
Microwaves
Infrared
Visible Light
Ultraviolet Rays
X-rays
Gamma Rays
QUIZ #1

16. Assignment:
1. Give five example of EM waves that we encounter in everyday life and give a
brief explanation.

17. Thank you !