CHAPTER 15. EM RADIATION 15.6
Chapter 15 — Summary
See the summary presentation ( Presentation: VPpxh at http://www.everythingscience.co.za)- Electromagnetic radiation has both a wave anda particle nature.
- Electromagnetic wavestravel at a speed of 3 × 108 m· s−^1 in a vacuum.
- The Electromagnetic spectrum consists of the following types of radiation: radio
waves, microwaves, infrared, visible, ultraviolet,X-rays, gamma-rays. - Gamma-rays have themost energy and are the most penetrating, while radio
waves have the lowest energy and are the least penetrating.
Chapter 15 End of Chapter Exercises
- What is the energy of a photon of EM radiation with a frequency of
3 × 108 Hz? - What is the energy of a photon of light with awavelength of 660 nm?
- List the main types of electromagnetic radiation in order of increasing
wavelength. - List the main uses of:
(a) radio waves
(b) infrared
(c) gamma rays
(d) X-rays - Explain why we need to protect ourselves from ultraviolet radiation
from the Sun. - List some advantagesand disadvantages of using X-rays.
- What precautions should we take when using cell phones?
- Write a short essay on a type of electromagnetic wave. You should
look at uses, advantagesand disadvantages of theradiation. - Explain why some types of electromagnetic radiation are more pene-
trating than others.
More practice video solutions or help at http://www.everythingscience.co.za(1.) 01md (2.) 01me (3.) 01mf (4.) 01mg (5.) 01mh (6.) 01mi
(7.) 01mj (8.) 01mk (9.) 01mm