(c) Electromagnetic Waves (self-study

Learning objectives

• state that all electromagnetic waves are transverse waves that travel with the same high speed in vacuum and state the magnitude of this speed

• describe the main components of the electromagnetic spectrum

• discuss the role of the following components in the stated applications:

1. radiowaves in radio and television communication

2. microwaves in satellite television and microwave oven

3. infra-red waves in infra-red remote controllers and intruder alarms

4. light in optical fibres for medical uses and telecommunications

5. ultra-violet in sunbeds, and sterilisation

6. X-rays in radiological and engineering applications

7. Gamma rays in medical treatment 

• describe the effects of absorbing electromagnetic waves, e.g. heating, ionisation and damage to living cells and tissue 

All of you knew about the nuclear crisis in Japan. 

What is actually so fearful about nuclear radiation? Why are radioactivity particles so dangerous? 

Are there any similarities between nuclear radiation and radiowaves? They are all classified as electromagnetic radiation. 

Harmful Effect of radiation on us